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1 | Two Sum | two-sum | <p>Given an array of integers <code>nums</code> and an integer <code>target</code>, return <em>indices of the two numbers such that they add up to <code>target</code></em>.</p>
<p>You may assume that each input would have <strong><em>exactly</em> one solution</strong>, and you may not use the <em>same</em> element twice.</p>
<p>You can return the answer in any order.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<strong>Input:</strong> nums = [2,7,11,15], target = 9
<strong>Output:</strong> [0,1]
<strong>Explanation:</strong> Because nums[0] + nums[1] == 9, we return [0, 1].
</pre>
<p><strong class="example">Example 2:</strong></p>
<pre>
<strong>Input:</strong> nums = [3,2,4], target = 6
<strong>Output:</strong> [1,2]
</pre>
<p><strong class="example">Example 3:</strong></p>
<pre>
<strong>Input:</strong> nums = [3,3], target = 6
<strong>Output:</strong> [0,1]
</pre>
<p> </p>
<p><strong>Constraints:</strong></p>
<ul>
<li><code>2 <= nums.length <= 10<sup>4</sup></code></li>
<li><code>-10<sup>9</sup> <= nums[i] <= 10<sup>9</sup></code></li>
<li><code>-10<sup>9</sup> <= target <= 10<sup>9</sup></code></li>
<li><strong>Only one valid answer exists.</strong></li>
</ul>
<p> </p>
<strong>Follow-up: </strong>Can you come up with an algorithm that is less than <code>O(n<sup>2</sup>)</code><font face="monospace"> </font>time complexity? | Easy | 16.8M | 30.3M | 16,787,625 | 30,334,274 | 55.3% | ['3sum', '4sum', 'two-sum-ii-input-array-is-sorted', 'two-sum-iii-data-structure-design', 'subarray-sum-equals-k', 'two-sum-iv-input-is-a-bst', 'two-sum-less-than-k', 'max-number-of-k-sum-pairs', 'count-good-meals', 'count-number-of-pairs-with-absolute-difference-k', 'number-of-pairs-of-strings-with-concatenation-equal-to-target', 'find-all-k-distant-indices-in-an-array', 'first-letter-to-appear-twice', 'number-of-excellent-pairs', 'number-of-arithmetic-triplets', 'node-with-highest-edge-score', 'check-distances-between-same-letters', 'find-subarrays-with-equal-sum', 'largest-positive-integer-that-exists-with-its-negative', 'number-of-distinct-averages', 'count-pairs-whose-sum-is-less-than-target'] | [] | Algorithms | [{"value": "cpp", "text": "C++", "defaultCode": "class Solution {\npublic:\n vector<int> twoSum(vector<int>& nums, int target) {\n \n }\n};"}, {"value": "java", "text": "Java", "defaultCode": "class Solution {\n public int[] twoSum(int[] nums, int target) {\n \n }\n}"}, {"value": "python", "text": "Python", "defaultCode": "class Solution(object):\n def twoSum(self, nums, target):\n \"\"\"\n :type nums: List[int]\n :type target: int\n :rtype: List[int]\n \"\"\"\n "}, {"value": "python3", "text": "Python3", "defaultCode": "class Solution:\n def twoSum(self, nums: List[int], target: int) -> List[int]:\n "}, {"value": "c", "text": "C", "defaultCode": "/**\n * Note: The returned array must be malloced, assume caller calls free().\n */\nint* twoSum(int* nums, int numsSize, int target, int* returnSize) {\n \n}"}, {"value": "csharp", "text": "C#", "defaultCode": "public class Solution {\n public int[] TwoSum(int[] nums, int target) {\n \n }\n}"}, {"value": "javascript", "text": "JavaScript", "defaultCode": "/**\n * @param {number[]} nums\n * @param {number} target\n * @return {number[]}\n */\nvar twoSum = function(nums, target) {\n \n};"}, {"value": "typescript", "text": "TypeScript", "defaultCode": "function twoSum(nums: number[], target: number): number[] {\n \n};"}, {"value": "php", "text": "PHP", "defaultCode": "class Solution {\n\n /**\n * @param Integer[] $nums\n * @param Integer $target\n * @return Integer[]\n */\n function twoSum($nums, $target) {\n \n }\n}"}, {"value": "swift", "text": "Swift", "defaultCode": "class Solution {\n func twoSum(_ nums: [Int], _ target: Int) -> [Int] {\n \n }\n}"}, {"value": "kotlin", "text": "Kotlin", "defaultCode": "class Solution {\n fun twoSum(nums: IntArray, target: Int): IntArray {\n \n }\n}"}, {"value": "dart", "text": "Dart", "defaultCode": "class Solution {\n List<int> twoSum(List<int> nums, int target) {\n \n }\n}"}, {"value": "golang", "text": "Go", "defaultCode": "func twoSum(nums []int, target int) []int {\n \n}"}, {"value": "ruby", "text": "Ruby", "defaultCode": "# @param {Integer[]} nums\n# @param {Integer} target\n# @return {Integer[]}\ndef two_sum(nums, target)\n \nend"}, {"value": "scala", "text": "Scala", "defaultCode": "object Solution {\n def twoSum(nums: Array[Int], target: Int): Array[Int] = {\n \n }\n}"}, {"value": "rust", "text": "Rust", "defaultCode": "impl Solution {\n pub fn two_sum(nums: Vec<i32>, target: i32) -> Vec<i32> {\n \n }\n}"}, {"value": "racket", "text": "Racket", "defaultCode": "(define/contract (two-sum nums target)\n (-> (listof exact-integer?) exact-integer? (listof exact-integer?))\n )"}, {"value": "erlang", "text": "Erlang", "defaultCode": "-spec two_sum(Nums :: [integer()], Target :: integer()) -> [integer()].\ntwo_sum(Nums, Target) ->\n ."}, {"value": "elixir", "text": "Elixir", "defaultCode": "defmodule Solution do\n @spec two_sum(nums :: [integer], target :: integer) :: [integer]\n def two_sum(nums, target) do\n \n end\nend"}] | [2,7,11,15]
9 | {
"name": "twoSum",
"params": [
{
"name": "nums",
"type": "integer[]"
},
{
"name": "target",
"type": "integer"
}
],
"return": {
"type": "integer[]",
"size": 2
},
"manual": false
} | {"cpp": ["C++", "<p>Compiled with <code> clang 19 </code> using the latest C++ 23 standard, and <code>libstdc++</code> provided by GCC 14.</p>\r\n\r\n<p>Your code is compiled with level two optimization (<code>-O2</code>). <a href=\"https://github.com/google/sanitizers/wiki/AddressSanitizer\" target=\"_blank\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>"], "java": ["Java", "<p><code>OpenJDK 21</code>. Using compile arguments: <code>--enable-preview --release 21</code></p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>\r\n<p>Includes <code>Pair</code> class from https://docs.oracle.com/javase/8/javafx/api/javafx/util/Pair.html.</p>"], "python": ["Python", "<p><code>Python 2.7.18</code>.</p>\r\n\r\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\"https://docs.python.org/2/library/array.html\" target=\"_blank\">array</a>, <a href=\"https://docs.python.org/2/library/bisect.html\" target=\"_blank\">bisect</a>, <a href=\"https://docs.python.org/2/library/collections.html\" target=\"_blank\">collections</a>. If you need more libraries, you can import it yourself.</p>\r\n\r\n<p>For Map/TreeMap data structure, you may use <a href=\"http://www.grantjenks.com/docs/sortedcontainers/\" target=\"_blank\">sortedcontainers</a> library.</p>\r\n\r\n<p>Note that Python 2.7 <a href=\"https://www.python.org/dev/peps/pep-0373/\" target=\"_blank\">is not maintained anymore</a>. For the latest Python, please choose Python3 instead.</p>"], "c": ["C", "<p>Compiled with <code>gcc 14</code> using the gnu11 standard.</p>\r\n\r\n<p>Your code is compiled with level one optimization (<code>-O2</code>). <a href=\"https://github.com/google/sanitizers/wiki/AddressSanitizer\" target=\"_blank\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>\r\n\r\n<p>For hash table operations, you may use <a href=\"https://troydhanson.github.io/uthash/\" target=\"_blank\">uthash</a>. \"uthash.h\" is included by default. Below are some examples:</p>\r\n\r\n<p><b>1. Adding an item to a hash.</b>\r\n<pre>\r\nstruct hash_entry {\r\n int id; /* we'll use this field as the key */\r\n char name[10];\r\n UT_hash_handle hh; /* makes this structure hashable */\r\n};\r\n\r\nstruct hash_entry *users = NULL;\r\n\r\nvoid add_user(struct hash_entry *s) {\r\n HASH_ADD_INT(users, id, s);\r\n}\r\n</pre>\r\n</p>\r\n\r\n<p><b>2. Looking up an item in a hash:</b>\r\n<pre>\r\nstruct hash_entry *find_user(int user_id) {\r\n struct hash_entry *s;\r\n HASH_FIND_INT(users, &user_id, s);\r\n return s;\r\n}\r\n</pre>\r\n</p>\r\n\r\n<p><b>3. Deleting an item in a hash:</b>\r\n<pre>\r\nvoid delete_user(struct hash_entry *user) {\r\n HASH_DEL(users, user); \r\n}\r\n</pre>\r\n</p>"], "csharp": ["C#", "<p><a href=\"https://learn.microsoft.com/en-us/dotnet/csharp/whats-new/csharp-13\" target=\"_blank\">C# 13</a> with .NET 9 runtime</p>"], "javascript": ["JavaScript", "<p><code>Node.js 22.14.0</code>.</p>\r\n\r\n<p>Your code is run with <code>--harmony</code> flag, enabling <a href=\"http://node.green/\" target=\"_blank\">new ES6 features</a>.</p>\r\n\r\n<p><a href=\"https://lodash.com\" target=\"_blank\">lodash.js</a> library is included by default.</p>\r\n\r\n<p>For Priority Queue / Queue data structures, you may use 6.3.2 version of <a href=\"https://github.com/datastructures-js/priority-queue/tree/v6.3.2\" target=\"_blank\">datastructures-js/priority-queue</a> and 4.2.3 version of <a href=\"https://github.com/datastructures-js/queue/tree/v4.2.3\" target=\"_blank\">datastructures-js/queue</a> and 1.0.4 version of <a href=\"https://github.com/datastructures-js/deque/tree/v1.0.4\" target=\"_blank\">datastructures-js/deque</a>.</p>"], "ruby": ["Ruby", "<p><code>Ruby 3.2</code></p>\r\n\r\n<p>Some common data structure implementations are provided in the Algorithms module: https://www.rubydoc.info/github/kanwei/algorithms/Algorithms</p>"], "swift": ["Swift", "<p><code>Swift 6.0</code>.</p>\r\n\r\n<p>You may use the following packages:<br/>\r\n<a href=\"https://github.com/apple/swift-algorithms/tree/1.2.0\" target=\"_blank\">swift-algorithms 1.2.0</a><br/>\r\n<a href=\"https://github.com/apple/swift-collections/tree/1.1.4\" target=\"_blank\">swift-collections 1.1.4</a><br/>\r\n<a href=\"https://github.com/apple/swift-numerics/tree/1.0.2\" target=\"_blank\">swift-numerics 1.0.2</a></p>"], "golang": ["Go", "<p><code>Go 1.23</code></p>\r\n<p>Support <a href=\"https://pkg.go.dev/github.com/emirpasic/[email protected]\" target=\"_blank\">https://pkg.go.dev/github.com/emirpasic/[email protected]</a> and <a href=\"https://pkg.go.dev/github.com/emirpasic/gods/[email protected]\" target=\"_blank\">https://pkg.go.dev/github.com/emirpasic/gods/[email protected]</a> library.</p>"], "python3": ["Python3", "<p><code>Python 3.11</code>.</p>\r\n\r\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\"https://docs.python.org/3/library/array.html\" target=\"_blank\">array</a>, <a href=\"https://docs.python.org/3/library/bisect.html\" target=\"_blank\">bisect</a>, <a href=\"https://docs.python.org/3/library/collections.html\" target=\"_blank\">collections</a>. If you need more libraries, you can import it yourself.</p>\r\n\r\n<p>For Map/TreeMap data structure, you may use <a href=\"http://www.grantjenks.com/docs/sortedcontainers/\" target=\"_blank\">sortedcontainers</a> library.</p>"], "scala": ["Scala", "<p><code>Scala 3.3.1</code>.</p>"], "kotlin": ["Kotlin", "<p><code>Kotlin 2.1.10</code>.</p>"], "rust": ["Rust", "<p><code>Rust 1.85.0</code>. Your code will be compiled with <code>opt-level</code> 2.</p>\r\n\r\n<p>Supports <a href=\"https://crates.io/crates/rand\" target=\"_blank\">rand v0.8</a> and <a href=\"https://crates.io/crates/regex\" target=\"_blank\">regex\u00a0v1</a> and <a href=\"https://crates.io/crates/itertools\" target=\"_blank\">itertools\u00a0v0.14</a> from crates.io</p>"], "php": ["PHP", "<p><code>PHP 8.2</code>.</p>\r\n<p>With bcmath module</p>"], "typescript": ["Typescript", "<p><code>TypeScript 5.7.3, Node.js 22.14.0</code>.</p>\r\n\r\n<p>Compile Options: <code>--alwaysStrict --strictBindCallApply --strictFunctionTypes --target ES2024</code></p>\r\n\r\n<p><a href=\"https://lodash.com\" target=\"_blank\">lodash.js</a> library is included by default.</p>\r\n\r\n<p>For Priority Queue / Queue data structures, you may use 6.3.2 version of <a href=\"https://github.com/datastructures-js/priority-queue/tree/v6.3.2\" target=\"_blank\">datastructures-js/priority-queue</a> and 4.2.3 version of <a href=\"https://github.com/datastructures-js/queue/tree/v4.2.3\" target=\"_blank\">datastructures-js/queue</a> and 1.0.4 version of <a href=\"https://github.com/datastructures-js/deque/tree/v1.0.4\" target=\"_blank\">datastructures-js/deque</a>.</p>"], "racket": ["Racket", "<p><a href=\"https://docs.racket-lang.org/guide/performance.html#%28tech._c%29\" target=\"_blank\">Racket CS</a> v8.15</p>\r\n\r\n<p>Using <code>#lang racket</code></p>\r\n\r\n<p>Required <code>data/gvector data/queue data/order data/heap</code> automatically for your convenience</p>"], "erlang": ["Erlang", "Erlang/OTP 26"], "elixir": ["Elixir", "Elixir 1.17 with Erlang/OTP 26"], "dart": ["Dart", "<p>Dart 3.2. You may use package <a href=\"https://pub.dev/packages/collection/versions/1.18.0\" target=\"_blank\">collection</a></p>\r\n\r\n<p>Your code will be run directly without compiling</p>"]} | ['Array', 'Hash Table'] |
2 | Add Two Numbers | add-two-numbers | <p>You are given two <strong>non-empty</strong> linked lists representing two non-negative integers. The digits are stored in <strong>reverse order</strong>, and each of their nodes contains a single digit. Add the two numbers and return the sum as a linked list.</p>
<p>You may assume the two numbers do not contain any leading zero, except the number 0 itself.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<img alt="" src="https://assets.leetcode.com/uploads/2020/10/02/addtwonumber1.jpg" style="width: 483px; height: 342px;" />
<pre>
<strong>Input:</strong> l1 = [2,4,3], l2 = [5,6,4]
<strong>Output:</strong> [7,0,8]
<strong>Explanation:</strong> 342 + 465 = 807.
</pre>
<p><strong class="example">Example 2:</strong></p>
<pre>
<strong>Input:</strong> l1 = [0], l2 = [0]
<strong>Output:</strong> [0]
</pre>
<p><strong class="example">Example 3:</strong></p>
<pre>
<strong>Input:</strong> l1 = [9,9,9,9,9,9,9], l2 = [9,9,9,9]
<strong>Output:</strong> [8,9,9,9,0,0,0,1]
</pre>
<p> </p>
<p><strong>Constraints:</strong></p>
<ul>
<li>The number of nodes in each linked list is in the range <code>[1, 100]</code>.</li>
<li><code>0 <= Node.val <= 9</code></li>
<li>It is guaranteed that the list represents a number that does not have leading zeros.</li>
</ul>
| Medium | 5.6M | 12.3M | 5,606,520 | 12,261,739 | 45.7% | ['multiply-strings', 'add-binary', 'sum-of-two-integers', 'add-strings', 'add-two-numbers-ii', 'add-to-array-form-of-integer', 'add-two-polynomials-represented-as-linked-lists', 'double-a-number-represented-as-a-linked-list'] | [] | Algorithms | [{"value": "cpp", "text": "C++", "defaultCode": "/**\n * Definition for singly-linked list.\n * struct ListNode {\n * int val;\n * ListNode *next;\n * ListNode() : val(0), next(nullptr) {}\n * ListNode(int x) : val(x), next(nullptr) {}\n * ListNode(int x, ListNode *next) : val(x), next(next) {}\n * };\n */\nclass Solution {\npublic:\n ListNode* addTwoNumbers(ListNode* l1, ListNode* l2) {\n \n }\n};"}, {"value": "java", "text": "Java", "defaultCode": "/**\n * Definition for singly-linked list.\n * public class ListNode {\n * int val;\n * ListNode next;\n * ListNode() {}\n * ListNode(int val) { this.val = val; }\n * ListNode(int val, ListNode next) { this.val = val; this.next = next; }\n * }\n */\nclass Solution {\n public ListNode addTwoNumbers(ListNode l1, ListNode l2) {\n \n }\n}"}, {"value": "python", "text": "Python", "defaultCode": "# Definition for singly-linked list.\n# class ListNode(object):\n# def __init__(self, val=0, next=None):\n# self.val = val\n# self.next = next\nclass Solution(object):\n def addTwoNumbers(self, l1, l2):\n \"\"\"\n :type l1: Optional[ListNode]\n :type l2: Optional[ListNode]\n :rtype: Optional[ListNode]\n \"\"\"\n "}, {"value": "python3", "text": "Python3", "defaultCode": "# Definition for singly-linked list.\n# class ListNode:\n# def __init__(self, val=0, next=None):\n# self.val = val\n# self.next = next\nclass Solution:\n def addTwoNumbers(self, l1: Optional[ListNode], l2: Optional[ListNode]) -> Optional[ListNode]:\n "}, {"value": "c", "text": "C", "defaultCode": "/**\n * Definition for singly-linked list.\n * struct ListNode {\n * int val;\n * struct ListNode *next;\n * };\n */\nstruct ListNode* addTwoNumbers(struct ListNode* l1, struct ListNode* l2) {\n \n}"}, {"value": "csharp", "text": "C#", "defaultCode": "/**\n * Definition for singly-linked list.\n * public class ListNode {\n * public int val;\n * public ListNode next;\n * public ListNode(int val=0, ListNode next=null) {\n * this.val = val;\n * this.next = next;\n * }\n * }\n */\npublic class Solution {\n public ListNode AddTwoNumbers(ListNode l1, ListNode l2) {\n \n }\n}"}, {"value": "javascript", "text": "JavaScript", "defaultCode": "/**\n * Definition for singly-linked list.\n * function ListNode(val, next) {\n * this.val = (val===undefined ? 0 : val)\n * this.next = (next===undefined ? null : next)\n * }\n */\n/**\n * @param {ListNode} l1\n * @param {ListNode} l2\n * @return {ListNode}\n */\nvar addTwoNumbers = function(l1, l2) {\n \n};"}, {"value": "typescript", "text": "TypeScript", "defaultCode": "/**\n * Definition for singly-linked list.\n * class ListNode {\n * val: number\n * next: ListNode | null\n * constructor(val?: number, next?: ListNode | null) {\n * this.val = (val===undefined ? 0 : val)\n * this.next = (next===undefined ? null : next)\n * }\n * }\n */\n\nfunction addTwoNumbers(l1: ListNode | null, l2: ListNode | null): ListNode | null {\n \n};"}, {"value": "php", "text": "PHP", "defaultCode": "/**\n * Definition for a singly-linked list.\n * class ListNode {\n * public $val = 0;\n * public $next = null;\n * function __construct($val = 0, $next = null) {\n * $this->val = $val;\n * $this->next = $next;\n * }\n * }\n */\nclass Solution {\n\n /**\n * @param ListNode $l1\n * @param ListNode $l2\n * @return ListNode\n */\n function addTwoNumbers($l1, $l2) {\n \n }\n}"}, {"value": "swift", "text": "Swift", "defaultCode": "/**\n * Definition for singly-linked list.\n * public class ListNode {\n * public var val: Int\n * public var next: ListNode?\n * public init() { self.val = 0; self.next = nil; }\n * public init(_ val: Int) { self.val = val; self.next = nil; }\n * public init(_ val: Int, _ next: ListNode?) { self.val = val; self.next = next; }\n * }\n */\nclass Solution {\n func addTwoNumbers(_ l1: ListNode?, _ l2: ListNode?) -> ListNode? {\n \n }\n}"}, {"value": "kotlin", "text": "Kotlin", "defaultCode": "/**\n * Example:\n * var li = ListNode(5)\n * var v = li.`val`\n * Definition for singly-linked list.\n * class ListNode(var `val`: Int) {\n * var next: ListNode? = null\n * }\n */\nclass Solution {\n fun addTwoNumbers(l1: ListNode?, l2: ListNode?): ListNode? {\n \n }\n}"}, {"value": "dart", "text": "Dart", "defaultCode": "/**\n * Definition for singly-linked list.\n * class ListNode {\n * int val;\n * ListNode? next;\n * ListNode([this.val = 0, this.next]);\n * }\n */\nclass Solution {\n ListNode? addTwoNumbers(ListNode? l1, ListNode? l2) {\n \n }\n}"}, {"value": "golang", "text": "Go", "defaultCode": "/**\n * Definition for singly-linked list.\n * type ListNode struct {\n * Val int\n * Next *ListNode\n * }\n */\nfunc addTwoNumbers(l1 *ListNode, l2 *ListNode) *ListNode {\n \n}"}, {"value": "ruby", "text": "Ruby", "defaultCode": "# Definition for singly-linked list.\n# class ListNode\n# attr_accessor :val, :next\n# def initialize(val = 0, _next = nil)\n# @val = val\n# @next = _next\n# end\n# end\n# @param {ListNode} l1\n# @param {ListNode} l2\n# @return {ListNode}\ndef add_two_numbers(l1, l2)\n \nend"}, {"value": "scala", "text": "Scala", "defaultCode": "/**\n * Definition for singly-linked list.\n * class ListNode(_x: Int = 0, _next: ListNode = null) {\n * var next: ListNode = _next\n * var x: Int = _x\n * }\n */\nobject Solution {\n def addTwoNumbers(l1: ListNode, l2: ListNode): ListNode = {\n \n }\n}"}, {"value": "rust", "text": "Rust", "defaultCode": "// Definition for singly-linked list.\n// #[derive(PartialEq, Eq, Clone, Debug)]\n// pub struct ListNode {\n// pub val: i32,\n// pub next: Option<Box<ListNode>>\n// }\n// \n// impl ListNode {\n// #[inline]\n// fn new(val: i32) -> Self {\n// ListNode {\n// next: None,\n// val\n// }\n// }\n// }\nimpl Solution {\n pub fn add_two_numbers(l1: Option<Box<ListNode>>, l2: Option<Box<ListNode>>) -> Option<Box<ListNode>> {\n \n }\n}"}, {"value": "racket", "text": "Racket", "defaultCode": "; Definition for singly-linked list:\n#|\n\n; val : integer?\n; next : (or/c list-node? #f)\n(struct list-node\n (val next) #:mutable #:transparent)\n\n; constructor\n(define (make-list-node [val 0])\n (list-node val #f))\n\n|#\n\n(define/contract (add-two-numbers l1 l2)\n (-> (or/c list-node? #f) (or/c list-node? #f) (or/c list-node? #f))\n )"}, {"value": "erlang", "text": "Erlang", "defaultCode": "%% Definition for singly-linked list.\n%%\n%% -record(list_node, {val = 0 :: integer(),\n%% next = null :: 'null' | #list_node{}}).\n\n-spec add_two_numbers(L1 :: #list_node{} | null, L2 :: #list_node{} | null) -> #list_node{} | null.\nadd_two_numbers(L1, L2) ->\n ."}, {"value": "elixir", "text": "Elixir", "defaultCode": "# Definition for singly-linked list.\n#\n# defmodule ListNode do\n# @type t :: %__MODULE__{\n# val: integer,\n# next: ListNode.t() | nil\n# }\n# defstruct val: 0, next: nil\n# end\n\ndefmodule Solution do\n @spec add_two_numbers(l1 :: ListNode.t | nil, l2 :: ListNode.t | nil) :: ListNode.t | nil\n def add_two_numbers(l1, l2) do\n \n end\nend"}] | [2,4,3]
[5,6,4] | {
"name": "addTwoNumbers",
"params": [
{
"name": "l1",
"type": "ListNode",
"dealloc": false
},
{
"name": "l2",
"type": "ListNode",
"dealloc": false
}
],
"return": {
"type": "ListNode",
"dealloc": true
}
} | {"cpp": ["C++", "<p>Compiled with <code> clang 19 </code> using the latest C++ 23 standard, and <code>libstdc++</code> provided by GCC 14.</p>\r\n\r\n<p>Your code is compiled with level two optimization (<code>-O2</code>). <a href=\"https://github.com/google/sanitizers/wiki/AddressSanitizer\" target=\"_blank\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>"], "java": ["Java", "<p><code>OpenJDK 21</code>. Using compile arguments: <code>--enable-preview --release 21</code></p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>\r\n<p>Includes <code>Pair</code> class from https://docs.oracle.com/javase/8/javafx/api/javafx/util/Pair.html.</p>"], "python": ["Python", "<p><code>Python 2.7.18</code>.</p>\r\n\r\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\"https://docs.python.org/2/library/array.html\" target=\"_blank\">array</a>, <a href=\"https://docs.python.org/2/library/bisect.html\" target=\"_blank\">bisect</a>, <a href=\"https://docs.python.org/2/library/collections.html\" target=\"_blank\">collections</a>. If you need more libraries, you can import it yourself.</p>\r\n\r\n<p>For Map/TreeMap data structure, you may use <a href=\"http://www.grantjenks.com/docs/sortedcontainers/\" target=\"_blank\">sortedcontainers</a> library.</p>\r\n\r\n<p>Note that Python 2.7 <a href=\"https://www.python.org/dev/peps/pep-0373/\" target=\"_blank\">is not maintained anymore</a>. For the latest Python, please choose Python3 instead.</p>"], "c": ["C", "<p>Compiled with <code>gcc 14</code> using the gnu11 standard.</p>\r\n\r\n<p>Your code is compiled with level one optimization (<code>-O2</code>). <a href=\"https://github.com/google/sanitizers/wiki/AddressSanitizer\" target=\"_blank\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>\r\n\r\n<p>For hash table operations, you may use <a href=\"https://troydhanson.github.io/uthash/\" target=\"_blank\">uthash</a>. \"uthash.h\" is included by default. Below are some examples:</p>\r\n\r\n<p><b>1. Adding an item to a hash.</b>\r\n<pre>\r\nstruct hash_entry {\r\n int id; /* we'll use this field as the key */\r\n char name[10];\r\n UT_hash_handle hh; /* makes this structure hashable */\r\n};\r\n\r\nstruct hash_entry *users = NULL;\r\n\r\nvoid add_user(struct hash_entry *s) {\r\n HASH_ADD_INT(users, id, s);\r\n}\r\n</pre>\r\n</p>\r\n\r\n<p><b>2. Looking up an item in a hash:</b>\r\n<pre>\r\nstruct hash_entry *find_user(int user_id) {\r\n struct hash_entry *s;\r\n HASH_FIND_INT(users, &user_id, s);\r\n return s;\r\n}\r\n</pre>\r\n</p>\r\n\r\n<p><b>3. Deleting an item in a hash:</b>\r\n<pre>\r\nvoid delete_user(struct hash_entry *user) {\r\n HASH_DEL(users, user); \r\n}\r\n</pre>\r\n</p>"], "csharp": ["C#", "<p><a href=\"https://learn.microsoft.com/en-us/dotnet/csharp/whats-new/csharp-13\" target=\"_blank\">C# 13</a> with .NET 9 runtime</p>"], "javascript": ["JavaScript", "<p><code>Node.js 22.14.0</code>.</p>\r\n\r\n<p>Your code is run with <code>--harmony</code> flag, enabling <a href=\"http://node.green/\" target=\"_blank\">new ES6 features</a>.</p>\r\n\r\n<p><a href=\"https://lodash.com\" target=\"_blank\">lodash.js</a> library is included by default.</p>\r\n\r\n<p>For Priority Queue / Queue data structures, you may use 6.3.2 version of <a href=\"https://github.com/datastructures-js/priority-queue/tree/v6.3.2\" target=\"_blank\">datastructures-js/priority-queue</a> and 4.2.3 version of <a href=\"https://github.com/datastructures-js/queue/tree/v4.2.3\" target=\"_blank\">datastructures-js/queue</a> and 1.0.4 version of <a href=\"https://github.com/datastructures-js/deque/tree/v1.0.4\" target=\"_blank\">datastructures-js/deque</a>.</p>"], "ruby": ["Ruby", "<p><code>Ruby 3.2</code></p>\r\n\r\n<p>Some common data structure implementations are provided in the Algorithms module: https://www.rubydoc.info/github/kanwei/algorithms/Algorithms</p>"], "swift": ["Swift", "<p><code>Swift 6.0</code>.</p>\r\n\r\n<p>You may use the following packages:<br/>\r\n<a href=\"https://github.com/apple/swift-algorithms/tree/1.2.0\" target=\"_blank\">swift-algorithms 1.2.0</a><br/>\r\n<a href=\"https://github.com/apple/swift-collections/tree/1.1.4\" target=\"_blank\">swift-collections 1.1.4</a><br/>\r\n<a href=\"https://github.com/apple/swift-numerics/tree/1.0.2\" target=\"_blank\">swift-numerics 1.0.2</a></p>"], "golang": ["Go", "<p><code>Go 1.23</code></p>\r\n<p>Support <a href=\"https://pkg.go.dev/github.com/emirpasic/[email protected]\" target=\"_blank\">https://pkg.go.dev/github.com/emirpasic/[email protected]</a> and <a href=\"https://pkg.go.dev/github.com/emirpasic/gods/[email protected]\" target=\"_blank\">https://pkg.go.dev/github.com/emirpasic/gods/[email protected]</a> library.</p>"], "python3": ["Python3", "<p><code>Python 3.11</code>.</p>\r\n\r\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\"https://docs.python.org/3/library/array.html\" target=\"_blank\">array</a>, <a href=\"https://docs.python.org/3/library/bisect.html\" target=\"_blank\">bisect</a>, <a href=\"https://docs.python.org/3/library/collections.html\" target=\"_blank\">collections</a>. If you need more libraries, you can import it yourself.</p>\r\n\r\n<p>For Map/TreeMap data structure, you may use <a href=\"http://www.grantjenks.com/docs/sortedcontainers/\" target=\"_blank\">sortedcontainers</a> library.</p>"], "scala": ["Scala", "<p><code>Scala 3.3.1</code>.</p>"], "kotlin": ["Kotlin", "<p><code>Kotlin 2.1.10</code>.</p>"], "rust": ["Rust", "<p><code>Rust 1.85.0</code>. Your code will be compiled with <code>opt-level</code> 2.</p>\r\n\r\n<p>Supports <a href=\"https://crates.io/crates/rand\" target=\"_blank\">rand v0.8</a> and <a href=\"https://crates.io/crates/regex\" target=\"_blank\">regex\u00a0v1</a> and <a href=\"https://crates.io/crates/itertools\" target=\"_blank\">itertools\u00a0v0.14</a> from crates.io</p>"], "php": ["PHP", "<p><code>PHP 8.2</code>.</p>\r\n<p>With bcmath module</p>"], "typescript": ["Typescript", "<p><code>TypeScript 5.7.3, Node.js 22.14.0</code>.</p>\r\n\r\n<p>Compile Options: <code>--alwaysStrict --strictBindCallApply --strictFunctionTypes --target ES2024</code></p>\r\n\r\n<p><a href=\"https://lodash.com\" target=\"_blank\">lodash.js</a> library is included by default.</p>\r\n\r\n<p>For Priority Queue / Queue data structures, you may use 6.3.2 version of <a href=\"https://github.com/datastructures-js/priority-queue/tree/v6.3.2\" target=\"_blank\">datastructures-js/priority-queue</a> and 4.2.3 version of <a href=\"https://github.com/datastructures-js/queue/tree/v4.2.3\" target=\"_blank\">datastructures-js/queue</a> and 1.0.4 version of <a href=\"https://github.com/datastructures-js/deque/tree/v1.0.4\" target=\"_blank\">datastructures-js/deque</a>.</p>"], "racket": ["Racket", "<p><a href=\"https://docs.racket-lang.org/guide/performance.html#%28tech._c%29\" target=\"_blank\">Racket CS</a> v8.15</p>\r\n\r\n<p>Using <code>#lang racket</code></p>\r\n\r\n<p>Required <code>data/gvector data/queue data/order data/heap</code> automatically for your convenience</p>"], "erlang": ["Erlang", "Erlang/OTP 26"], "elixir": ["Elixir", "Elixir 1.17 with Erlang/OTP 26"], "dart": ["Dart", "<p>Dart 3.2. You may use package <a href=\"https://pub.dev/packages/collection/versions/1.18.0\" target=\"_blank\">collection</a></p>\r\n\r\n<p>Your code will be run directly without compiling</p>"]} | ['Linked List', 'Math', 'Recursion'] |
3 | Longest Substring Without Repeating Characters | longest-substring-without-repeating-characters | <p>Given a string <code>s</code>, find the length of the <strong>longest</strong> <span data-keyword="substring-nonempty"><strong>substring</strong></span> without duplicate characters.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<strong>Input:</strong> s = "abcabcbb"
<strong>Output:</strong> 3
<strong>Explanation:</strong> The answer is "abc", with the length of 3.
</pre>
<p><strong class="example">Example 2:</strong></p>
<pre>
<strong>Input:</strong> s = "bbbbb"
<strong>Output:</strong> 1
<strong>Explanation:</strong> The answer is "b", with the length of 1.
</pre>
<p><strong class="example">Example 3:</strong></p>
<pre>
<strong>Input:</strong> s = "pwwkew"
<strong>Output:</strong> 3
<strong>Explanation:</strong> The answer is "wke", with the length of 3.
Notice that the answer must be a substring, "pwke" is a subsequence and not a substring.
</pre>
<p> </p>
<p><strong>Constraints:</strong></p>
<ul>
<li><code>0 <= s.length <= 5 * 10<sup>4</sup></code></li>
<li><code>s</code> consists of English letters, digits, symbols and spaces.</li>
</ul>
| Medium | 7.2M | 19.8M | 7,234,473 | 19,794,857 | 36.5% | ['longest-substring-with-at-most-two-distinct-characters', 'longest-substring-with-at-most-k-distinct-characters', 'subarrays-with-k-different-integers', 'maximum-erasure-value', 'number-of-equal-count-substrings', 'minimum-consecutive-cards-to-pick-up', 'longest-nice-subarray', 'optimal-partition-of-string', 'count-complete-subarrays-in-an-array', 'find-longest-special-substring-that-occurs-thrice-ii', 'find-longest-special-substring-that-occurs-thrice-i'] | [] | Algorithms | [{"value": "cpp", "text": "C++", "defaultCode": "class Solution {\npublic:\n int lengthOfLongestSubstring(string s) {\n \n }\n};"}, {"value": "java", "text": "Java", "defaultCode": "class Solution {\n public int lengthOfLongestSubstring(String s) {\n \n }\n}"}, {"value": "python", "text": "Python", "defaultCode": "class Solution(object):\n def lengthOfLongestSubstring(self, s):\n \"\"\"\n :type s: str\n :rtype: int\n \"\"\"\n "}, {"value": "python3", "text": "Python3", "defaultCode": "class Solution:\n def lengthOfLongestSubstring(self, s: str) -> int:\n "}, {"value": "c", "text": "C", "defaultCode": "int lengthOfLongestSubstring(char* s) {\n \n}"}, {"value": "csharp", "text": "C#", "defaultCode": "public class Solution {\n public int LengthOfLongestSubstring(string s) {\n \n }\n}"}, {"value": "javascript", "text": "JavaScript", "defaultCode": "/**\n * @param {string} s\n * @return {number}\n */\nvar lengthOfLongestSubstring = function(s) {\n \n};"}, {"value": "typescript", "text": "TypeScript", "defaultCode": "function lengthOfLongestSubstring(s: string): number {\n \n};"}, {"value": "php", "text": "PHP", "defaultCode": "class Solution {\n\n /**\n * @param String $s\n * @return Integer\n */\n function lengthOfLongestSubstring($s) {\n \n }\n}"}, {"value": "swift", "text": "Swift", "defaultCode": "class Solution {\n func lengthOfLongestSubstring(_ s: String) -> Int {\n \n }\n}"}, {"value": "kotlin", "text": "Kotlin", "defaultCode": "class Solution {\n fun lengthOfLongestSubstring(s: String): Int {\n \n }\n}"}, {"value": "dart", "text": "Dart", "defaultCode": "class Solution {\n int lengthOfLongestSubstring(String s) {\n \n }\n}"}, {"value": "golang", "text": "Go", "defaultCode": "func lengthOfLongestSubstring(s string) int {\n \n}"}, {"value": "ruby", "text": "Ruby", "defaultCode": "# @param {String} s\n# @return {Integer}\ndef length_of_longest_substring(s)\n \nend"}, {"value": "scala", "text": "Scala", "defaultCode": "object Solution {\n def lengthOfLongestSubstring(s: String): Int = {\n \n }\n}"}, {"value": "rust", "text": "Rust", "defaultCode": "impl Solution {\n pub fn length_of_longest_substring(s: String) -> i32 {\n \n }\n}"}, {"value": "racket", "text": "Racket", "defaultCode": "(define/contract (length-of-longest-substring s)\n (-> string? exact-integer?)\n )"}, {"value": "erlang", "text": "Erlang", "defaultCode": "-spec length_of_longest_substring(S :: unicode:unicode_binary()) -> integer().\nlength_of_longest_substring(S) ->\n ."}, {"value": "elixir", "text": "Elixir", "defaultCode": "defmodule Solution do\n @spec length_of_longest_substring(s :: String.t) :: integer\n def length_of_longest_substring(s) do\n \n end\nend"}] | "abcabcbb" | {
"name": "lengthOfLongestSubstring",
"params": [
{
"name": "s",
"type": "string"
}
],
"return": {
"type": "integer"
}
} | {"cpp": ["C++", "<p>Compiled with <code> clang 19 </code> using the latest C++ 23 standard, and <code>libstdc++</code> provided by GCC 14.</p>\r\n\r\n<p>Your code is compiled with level two optimization (<code>-O2</code>). <a href=\"https://github.com/google/sanitizers/wiki/AddressSanitizer\" target=\"_blank\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>"], "java": ["Java", "<p><code>OpenJDK 21</code>. Using compile arguments: <code>--enable-preview --release 21</code></p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>\r\n<p>Includes <code>Pair</code> class from https://docs.oracle.com/javase/8/javafx/api/javafx/util/Pair.html.</p>"], "python": ["Python", "<p><code>Python 2.7.18</code>.</p>\r\n\r\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\"https://docs.python.org/2/library/array.html\" target=\"_blank\">array</a>, <a href=\"https://docs.python.org/2/library/bisect.html\" target=\"_blank\">bisect</a>, <a href=\"https://docs.python.org/2/library/collections.html\" target=\"_blank\">collections</a>. If you need more libraries, you can import it yourself.</p>\r\n\r\n<p>For Map/TreeMap data structure, you may use <a href=\"http://www.grantjenks.com/docs/sortedcontainers/\" target=\"_blank\">sortedcontainers</a> library.</p>\r\n\r\n<p>Note that Python 2.7 <a href=\"https://www.python.org/dev/peps/pep-0373/\" target=\"_blank\">is not maintained anymore</a>. For the latest Python, please choose Python3 instead.</p>"], "c": ["C", "<p>Compiled with <code>gcc 14</code> using the gnu11 standard.</p>\r\n\r\n<p>Your code is compiled with level one optimization (<code>-O2</code>). <a href=\"https://github.com/google/sanitizers/wiki/AddressSanitizer\" target=\"_blank\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>\r\n\r\n<p>For hash table operations, you may use <a href=\"https://troydhanson.github.io/uthash/\" target=\"_blank\">uthash</a>. \"uthash.h\" is included by default. Below are some examples:</p>\r\n\r\n<p><b>1. Adding an item to a hash.</b>\r\n<pre>\r\nstruct hash_entry {\r\n int id; /* we'll use this field as the key */\r\n char name[10];\r\n UT_hash_handle hh; /* makes this structure hashable */\r\n};\r\n\r\nstruct hash_entry *users = NULL;\r\n\r\nvoid add_user(struct hash_entry *s) {\r\n HASH_ADD_INT(users, id, s);\r\n}\r\n</pre>\r\n</p>\r\n\r\n<p><b>2. Looking up an item in a hash:</b>\r\n<pre>\r\nstruct hash_entry *find_user(int user_id) {\r\n struct hash_entry *s;\r\n HASH_FIND_INT(users, &user_id, s);\r\n return s;\r\n}\r\n</pre>\r\n</p>\r\n\r\n<p><b>3. Deleting an item in a hash:</b>\r\n<pre>\r\nvoid delete_user(struct hash_entry *user) {\r\n HASH_DEL(users, user); \r\n}\r\n</pre>\r\n</p>"], "csharp": ["C#", "<p><a href=\"https://learn.microsoft.com/en-us/dotnet/csharp/whats-new/csharp-13\" target=\"_blank\">C# 13</a> with .NET 9 runtime</p>"], "javascript": ["JavaScript", "<p><code>Node.js 22.14.0</code>.</p>\r\n\r\n<p>Your code is run with <code>--harmony</code> flag, enabling <a href=\"http://node.green/\" target=\"_blank\">new ES6 features</a>.</p>\r\n\r\n<p><a href=\"https://lodash.com\" target=\"_blank\">lodash.js</a> library is included by default.</p>\r\n\r\n<p>For Priority Queue / Queue data structures, you may use 6.3.2 version of <a href=\"https://github.com/datastructures-js/priority-queue/tree/v6.3.2\" target=\"_blank\">datastructures-js/priority-queue</a> and 4.2.3 version of <a href=\"https://github.com/datastructures-js/queue/tree/v4.2.3\" target=\"_blank\">datastructures-js/queue</a> and 1.0.4 version of <a href=\"https://github.com/datastructures-js/deque/tree/v1.0.4\" target=\"_blank\">datastructures-js/deque</a>.</p>"], "ruby": ["Ruby", "<p><code>Ruby 3.2</code></p>\r\n\r\n<p>Some common data structure implementations are provided in the Algorithms module: https://www.rubydoc.info/github/kanwei/algorithms/Algorithms</p>"], "swift": ["Swift", "<p><code>Swift 6.0</code>.</p>\r\n\r\n<p>You may use the following packages:<br/>\r\n<a href=\"https://github.com/apple/swift-algorithms/tree/1.2.0\" target=\"_blank\">swift-algorithms 1.2.0</a><br/>\r\n<a href=\"https://github.com/apple/swift-collections/tree/1.1.4\" target=\"_blank\">swift-collections 1.1.4</a><br/>\r\n<a href=\"https://github.com/apple/swift-numerics/tree/1.0.2\" target=\"_blank\">swift-numerics 1.0.2</a></p>"], "golang": ["Go", "<p><code>Go 1.23</code></p>\r\n<p>Support <a href=\"https://pkg.go.dev/github.com/emirpasic/[email protected]\" target=\"_blank\">https://pkg.go.dev/github.com/emirpasic/[email protected]</a> and <a href=\"https://pkg.go.dev/github.com/emirpasic/gods/[email protected]\" target=\"_blank\">https://pkg.go.dev/github.com/emirpasic/gods/[email protected]</a> library.</p>"], "python3": ["Python3", "<p><code>Python 3.11</code>.</p>\r\n\r\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\"https://docs.python.org/3/library/array.html\" target=\"_blank\">array</a>, <a href=\"https://docs.python.org/3/library/bisect.html\" target=\"_blank\">bisect</a>, <a href=\"https://docs.python.org/3/library/collections.html\" target=\"_blank\">collections</a>. If you need more libraries, you can import it yourself.</p>\r\n\r\n<p>For Map/TreeMap data structure, you may use <a href=\"http://www.grantjenks.com/docs/sortedcontainers/\" target=\"_blank\">sortedcontainers</a> library.</p>"], "scala": ["Scala", "<p><code>Scala 3.3.1</code>.</p>"], "kotlin": ["Kotlin", "<p><code>Kotlin 2.1.10</code>.</p>"], "rust": ["Rust", "<p><code>Rust 1.85.0</code>. Your code will be compiled with <code>opt-level</code> 2.</p>\r\n\r\n<p>Supports <a href=\"https://crates.io/crates/rand\" target=\"_blank\">rand v0.8</a> and <a href=\"https://crates.io/crates/regex\" target=\"_blank\">regex\u00a0v1</a> and <a href=\"https://crates.io/crates/itertools\" target=\"_blank\">itertools\u00a0v0.14</a> from crates.io</p>"], "php": ["PHP", "<p><code>PHP 8.2</code>.</p>\r\n<p>With bcmath module</p>"], "typescript": ["Typescript", "<p><code>TypeScript 5.7.3, Node.js 22.14.0</code>.</p>\r\n\r\n<p>Compile Options: <code>--alwaysStrict --strictBindCallApply --strictFunctionTypes --target ES2024</code></p>\r\n\r\n<p><a href=\"https://lodash.com\" target=\"_blank\">lodash.js</a> library is included by default.</p>\r\n\r\n<p>For Priority Queue / Queue data structures, you may use 6.3.2 version of <a href=\"https://github.com/datastructures-js/priority-queue/tree/v6.3.2\" target=\"_blank\">datastructures-js/priority-queue</a> and 4.2.3 version of <a href=\"https://github.com/datastructures-js/queue/tree/v4.2.3\" target=\"_blank\">datastructures-js/queue</a> and 1.0.4 version of <a href=\"https://github.com/datastructures-js/deque/tree/v1.0.4\" target=\"_blank\">datastructures-js/deque</a>.</p>"], "racket": ["Racket", "<p><a href=\"https://docs.racket-lang.org/guide/performance.html#%28tech._c%29\" target=\"_blank\">Racket CS</a> v8.15</p>\r\n\r\n<p>Using <code>#lang racket</code></p>\r\n\r\n<p>Required <code>data/gvector data/queue data/order data/heap</code> automatically for your convenience</p>"], "erlang": ["Erlang", "Erlang/OTP 26"], "elixir": ["Elixir", "Elixir 1.17 with Erlang/OTP 26"], "dart": ["Dart", "<p>Dart 3.2. You may use package <a href=\"https://pub.dev/packages/collection/versions/1.18.0\" target=\"_blank\">collection</a></p>\r\n\r\n<p>Your code will be run directly without compiling</p>"]} | ['Hash Table', 'String', 'Sliding Window'] |
4 | Median of Two Sorted Arrays | median-of-two-sorted-arrays | <p>Given two sorted arrays <code>nums1</code> and <code>nums2</code> of size <code>m</code> and <code>n</code> respectively, return <strong>the median</strong> of the two sorted arrays.</p>
<p>The overall run time complexity should be <code>O(log (m+n))</code>.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<strong>Input:</strong> nums1 = [1,3], nums2 = [2]
<strong>Output:</strong> 2.00000
<strong>Explanation:</strong> merged array = [1,2,3] and median is 2.
</pre>
<p><strong class="example">Example 2:</strong></p>
<pre>
<strong>Input:</strong> nums1 = [1,2], nums2 = [3,4]
<strong>Output:</strong> 2.50000
<strong>Explanation:</strong> merged array = [1,2,3,4] and median is (2 + 3) / 2 = 2.5.
</pre>
<p> </p>
<p><strong>Constraints:</strong></p>
<ul>
<li><code>nums1.length == m</code></li>
<li><code>nums2.length == n</code></li>
<li><code>0 <= m <= 1000</code></li>
<li><code>0 <= n <= 1000</code></li>
<li><code>1 <= m + n <= 2000</code></li>
<li><code>-10<sup>6</sup> <= nums1[i], nums2[i] <= 10<sup>6</sup></code></li>
</ul>
| Hard | 3.3M | 7.6M | 3,284,688 | 7,596,612 | 43.2% | ['median-of-a-row-wise-sorted-matrix'] | [] | Algorithms | [{"value": "cpp", "text": "C++", "defaultCode": "class Solution {\npublic:\n double findMedianSortedArrays(vector<int>& nums1, vector<int>& nums2) {\n \n }\n};"}, {"value": "java", "text": "Java", "defaultCode": "class Solution {\n public double findMedianSortedArrays(int[] nums1, int[] nums2) {\n \n }\n}"}, {"value": "python", "text": "Python", "defaultCode": "class Solution(object):\n def findMedianSortedArrays(self, nums1, nums2):\n \"\"\"\n :type nums1: List[int]\n :type nums2: List[int]\n :rtype: float\n \"\"\"\n "}, {"value": "python3", "text": "Python3", "defaultCode": "class Solution:\n def findMedianSortedArrays(self, nums1: List[int], nums2: List[int]) -> float:\n "}, {"value": "c", "text": "C", "defaultCode": "double findMedianSortedArrays(int* nums1, int nums1Size, int* nums2, int nums2Size) {\n \n}"}, {"value": "csharp", "text": "C#", "defaultCode": "public class Solution {\n public double FindMedianSortedArrays(int[] nums1, int[] nums2) {\n \n }\n}"}, {"value": "javascript", "text": "JavaScript", "defaultCode": "/**\n * @param {number[]} nums1\n * @param {number[]} nums2\n * @return {number}\n */\nvar findMedianSortedArrays = function(nums1, nums2) {\n \n};"}, {"value": "typescript", "text": "TypeScript", "defaultCode": "function findMedianSortedArrays(nums1: number[], nums2: number[]): number {\n \n};"}, {"value": "php", "text": "PHP", "defaultCode": "class Solution {\n\n /**\n * @param Integer[] $nums1\n * @param Integer[] $nums2\n * @return Float\n */\n function findMedianSortedArrays($nums1, $nums2) {\n \n }\n}"}, {"value": "swift", "text": "Swift", "defaultCode": "class Solution {\n func findMedianSortedArrays(_ nums1: [Int], _ nums2: [Int]) -> Double {\n \n }\n}"}, {"value": "kotlin", "text": "Kotlin", "defaultCode": "class Solution {\n fun findMedianSortedArrays(nums1: IntArray, nums2: IntArray): Double {\n \n }\n}"}, {"value": "dart", "text": "Dart", "defaultCode": "class Solution {\n double findMedianSortedArrays(List<int> nums1, List<int> nums2) {\n \n }\n}"}, {"value": "golang", "text": "Go", "defaultCode": "func findMedianSortedArrays(nums1 []int, nums2 []int) float64 {\n \n}"}, {"value": "ruby", "text": "Ruby", "defaultCode": "# @param {Integer[]} nums1\n# @param {Integer[]} nums2\n# @return {Float}\ndef find_median_sorted_arrays(nums1, nums2)\n \nend"}, {"value": "scala", "text": "Scala", "defaultCode": "object Solution {\n def findMedianSortedArrays(nums1: Array[Int], nums2: Array[Int]): Double = {\n \n }\n}"}, {"value": "rust", "text": "Rust", "defaultCode": "impl Solution {\n pub fn find_median_sorted_arrays(nums1: Vec<i32>, nums2: Vec<i32>) -> f64 {\n \n }\n}"}, {"value": "racket", "text": "Racket", "defaultCode": "(define/contract (find-median-sorted-arrays nums1 nums2)\n (-> (listof exact-integer?) (listof exact-integer?) flonum?)\n )"}, {"value": "erlang", "text": "Erlang", "defaultCode": "-spec find_median_sorted_arrays(Nums1 :: [integer()], Nums2 :: [integer()]) -> float().\nfind_median_sorted_arrays(Nums1, Nums2) ->\n ."}, {"value": "elixir", "text": "Elixir", "defaultCode": "defmodule Solution do\n @spec find_median_sorted_arrays(nums1 :: [integer], nums2 :: [integer]) :: float\n def find_median_sorted_arrays(nums1, nums2) do\n \n end\nend"}] | [1,3]
[2] | {
"name": "findMedianSortedArrays",
"params": [
{
"name": "nums1",
"type": "integer[]"
},
{
"name": "nums2",
"type": "integer[]"
}
],
"return": {
"type": "double"
}
} | {"cpp": ["C++", "<p>Compiled with <code> clang 19 </code> using the latest C++ 23 standard, and <code>libstdc++</code> provided by GCC 14.</p>\r\n\r\n<p>Your code is compiled with level two optimization (<code>-O2</code>). <a href=\"https://github.com/google/sanitizers/wiki/AddressSanitizer\" target=\"_blank\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>"], "java": ["Java", "<p><code>OpenJDK 21</code>. Using compile arguments: <code>--enable-preview --release 21</code></p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>\r\n<p>Includes <code>Pair</code> class from https://docs.oracle.com/javase/8/javafx/api/javafx/util/Pair.html.</p>"], "python": ["Python", "<p><code>Python 2.7.18</code>.</p>\r\n\r\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\"https://docs.python.org/2/library/array.html\" target=\"_blank\">array</a>, <a href=\"https://docs.python.org/2/library/bisect.html\" target=\"_blank\">bisect</a>, <a href=\"https://docs.python.org/2/library/collections.html\" target=\"_blank\">collections</a>. If you need more libraries, you can import it yourself.</p>\r\n\r\n<p>For Map/TreeMap data structure, you may use <a href=\"http://www.grantjenks.com/docs/sortedcontainers/\" target=\"_blank\">sortedcontainers</a> library.</p>\r\n\r\n<p>Note that Python 2.7 <a href=\"https://www.python.org/dev/peps/pep-0373/\" target=\"_blank\">is not maintained anymore</a>. For the latest Python, please choose Python3 instead.</p>"], "c": ["C", "<p>Compiled with <code>gcc 14</code> using the gnu11 standard.</p>\r\n\r\n<p>Your code is compiled with level one optimization (<code>-O2</code>). <a href=\"https://github.com/google/sanitizers/wiki/AddressSanitizer\" target=\"_blank\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>\r\n\r\n<p>For hash table operations, you may use <a href=\"https://troydhanson.github.io/uthash/\" target=\"_blank\">uthash</a>. \"uthash.h\" is included by default. Below are some examples:</p>\r\n\r\n<p><b>1. Adding an item to a hash.</b>\r\n<pre>\r\nstruct hash_entry {\r\n int id; /* we'll use this field as the key */\r\n char name[10];\r\n UT_hash_handle hh; /* makes this structure hashable */\r\n};\r\n\r\nstruct hash_entry *users = NULL;\r\n\r\nvoid add_user(struct hash_entry *s) {\r\n HASH_ADD_INT(users, id, s);\r\n}\r\n</pre>\r\n</p>\r\n\r\n<p><b>2. Looking up an item in a hash:</b>\r\n<pre>\r\nstruct hash_entry *find_user(int user_id) {\r\n struct hash_entry *s;\r\n HASH_FIND_INT(users, &user_id, s);\r\n return s;\r\n}\r\n</pre>\r\n</p>\r\n\r\n<p><b>3. Deleting an item in a hash:</b>\r\n<pre>\r\nvoid delete_user(struct hash_entry *user) {\r\n HASH_DEL(users, user); \r\n}\r\n</pre>\r\n</p>"], "csharp": ["C#", "<p><a href=\"https://learn.microsoft.com/en-us/dotnet/csharp/whats-new/csharp-13\" target=\"_blank\">C# 13</a> with .NET 9 runtime</p>"], "javascript": ["JavaScript", "<p><code>Node.js 22.14.0</code>.</p>\r\n\r\n<p>Your code is run with <code>--harmony</code> flag, enabling <a href=\"http://node.green/\" target=\"_blank\">new ES6 features</a>.</p>\r\n\r\n<p><a href=\"https://lodash.com\" target=\"_blank\">lodash.js</a> library is included by default.</p>\r\n\r\n<p>For Priority Queue / Queue data structures, you may use 6.3.2 version of <a href=\"https://github.com/datastructures-js/priority-queue/tree/v6.3.2\" target=\"_blank\">datastructures-js/priority-queue</a> and 4.2.3 version of <a href=\"https://github.com/datastructures-js/queue/tree/v4.2.3\" target=\"_blank\">datastructures-js/queue</a> and 1.0.4 version of <a href=\"https://github.com/datastructures-js/deque/tree/v1.0.4\" target=\"_blank\">datastructures-js/deque</a>.</p>"], "ruby": ["Ruby", "<p><code>Ruby 3.2</code></p>\r\n\r\n<p>Some common data structure implementations are provided in the Algorithms module: https://www.rubydoc.info/github/kanwei/algorithms/Algorithms</p>"], "swift": ["Swift", "<p><code>Swift 6.0</code>.</p>\r\n\r\n<p>You may use the following packages:<br/>\r\n<a href=\"https://github.com/apple/swift-algorithms/tree/1.2.0\" target=\"_blank\">swift-algorithms 1.2.0</a><br/>\r\n<a href=\"https://github.com/apple/swift-collections/tree/1.1.4\" target=\"_blank\">swift-collections 1.1.4</a><br/>\r\n<a href=\"https://github.com/apple/swift-numerics/tree/1.0.2\" target=\"_blank\">swift-numerics 1.0.2</a></p>"], "golang": ["Go", "<p><code>Go 1.23</code></p>\r\n<p>Support <a href=\"https://pkg.go.dev/github.com/emirpasic/[email protected]\" target=\"_blank\">https://pkg.go.dev/github.com/emirpasic/[email protected]</a> and <a href=\"https://pkg.go.dev/github.com/emirpasic/gods/[email protected]\" target=\"_blank\">https://pkg.go.dev/github.com/emirpasic/gods/[email protected]</a> library.</p>"], "python3": ["Python3", "<p><code>Python 3.11</code>.</p>\r\n\r\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\"https://docs.python.org/3/library/array.html\" target=\"_blank\">array</a>, <a href=\"https://docs.python.org/3/library/bisect.html\" target=\"_blank\">bisect</a>, <a href=\"https://docs.python.org/3/library/collections.html\" target=\"_blank\">collections</a>. If you need more libraries, you can import it yourself.</p>\r\n\r\n<p>For Map/TreeMap data structure, you may use <a href=\"http://www.grantjenks.com/docs/sortedcontainers/\" target=\"_blank\">sortedcontainers</a> library.</p>"], "scala": ["Scala", "<p><code>Scala 3.3.1</code>.</p>"], "kotlin": ["Kotlin", "<p><code>Kotlin 2.1.10</code>.</p>"], "rust": ["Rust", "<p><code>Rust 1.85.0</code>. Your code will be compiled with <code>opt-level</code> 2.</p>\r\n\r\n<p>Supports <a href=\"https://crates.io/crates/rand\" target=\"_blank\">rand v0.8</a> and <a href=\"https://crates.io/crates/regex\" target=\"_blank\">regex\u00a0v1</a> and <a href=\"https://crates.io/crates/itertools\" target=\"_blank\">itertools\u00a0v0.14</a> from crates.io</p>"], "php": ["PHP", "<p><code>PHP 8.2</code>.</p>\r\n<p>With bcmath module</p>"], "typescript": ["Typescript", "<p><code>TypeScript 5.7.3, Node.js 22.14.0</code>.</p>\r\n\r\n<p>Compile Options: <code>--alwaysStrict --strictBindCallApply --strictFunctionTypes --target ES2024</code></p>\r\n\r\n<p><a href=\"https://lodash.com\" target=\"_blank\">lodash.js</a> library is included by default.</p>\r\n\r\n<p>For Priority Queue / Queue data structures, you may use 6.3.2 version of <a href=\"https://github.com/datastructures-js/priority-queue/tree/v6.3.2\" target=\"_blank\">datastructures-js/priority-queue</a> and 4.2.3 version of <a href=\"https://github.com/datastructures-js/queue/tree/v4.2.3\" target=\"_blank\">datastructures-js/queue</a> and 1.0.4 version of <a href=\"https://github.com/datastructures-js/deque/tree/v1.0.4\" target=\"_blank\">datastructures-js/deque</a>.</p>"], "racket": ["Racket", "<p><a href=\"https://docs.racket-lang.org/guide/performance.html#%28tech._c%29\" target=\"_blank\">Racket CS</a> v8.15</p>\r\n\r\n<p>Using <code>#lang racket</code></p>\r\n\r\n<p>Required <code>data/gvector data/queue data/order data/heap</code> automatically for your convenience</p>"], "erlang": ["Erlang", "Erlang/OTP 26"], "elixir": ["Elixir", "Elixir 1.17 with Erlang/OTP 26"], "dart": ["Dart", "<p>Dart 3.2. You may use package <a href=\"https://pub.dev/packages/collection/versions/1.18.0\" target=\"_blank\">collection</a></p>\r\n\r\n<p>Your code will be run directly without compiling</p>"]} | ['Array', 'Binary Search', 'Divide and Conquer'] |
5 | Longest Palindromic Substring | longest-palindromic-substring | <p>Given a string <code>s</code>, return <em>the longest</em> <span data-keyword="palindromic-string"><em>palindromic</em></span> <span data-keyword="substring-nonempty"><em>substring</em></span> in <code>s</code>.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<strong>Input:</strong> s = "babad"
<strong>Output:</strong> "bab"
<strong>Explanation:</strong> "aba" is also a valid answer.
</pre>
<p><strong class="example">Example 2:</strong></p>
<pre>
<strong>Input:</strong> s = "cbbd"
<strong>Output:</strong> "bb"
</pre>
<p> </p>
<p><strong>Constraints:</strong></p>
<ul>
<li><code>1 <= s.length <= 1000</code></li>
<li><code>s</code> consist of only digits and English letters.</li>
</ul>
| Medium | 3.7M | 10.5M | 3,742,977 | 10,545,358 | 35.5% | ['shortest-palindrome', 'palindrome-permutation', 'palindrome-pairs', 'longest-palindromic-subsequence', 'palindromic-substrings', 'maximum-number-of-non-overlapping-palindrome-substrings'] | [] | Algorithms | [{"value": "cpp", "text": "C++", "defaultCode": "class Solution {\npublic:\n string longestPalindrome(string s) {\n \n }\n};"}, {"value": "java", "text": "Java", "defaultCode": "class Solution {\n public String longestPalindrome(String s) {\n \n }\n}"}, {"value": "python", "text": "Python", "defaultCode": "class Solution(object):\n def longestPalindrome(self, s):\n \"\"\"\n :type s: str\n :rtype: str\n \"\"\"\n "}, {"value": "python3", "text": "Python3", "defaultCode": "class Solution:\n def longestPalindrome(self, s: str) -> str:\n "}, {"value": "c", "text": "C", "defaultCode": "char* longestPalindrome(char* s) {\n \n}"}, {"value": "csharp", "text": "C#", "defaultCode": "public class Solution {\n public string LongestPalindrome(string s) {\n \n }\n}"}, {"value": "javascript", "text": "JavaScript", "defaultCode": "/**\n * @param {string} s\n * @return {string}\n */\nvar longestPalindrome = function(s) {\n \n};"}, {"value": "typescript", "text": "TypeScript", "defaultCode": "function longestPalindrome(s: string): string {\n \n};"}, {"value": "php", "text": "PHP", "defaultCode": "class Solution {\n\n /**\n * @param String $s\n * @return String\n */\n function longestPalindrome($s) {\n \n }\n}"}, {"value": "swift", "text": "Swift", "defaultCode": "class Solution {\n func longestPalindrome(_ s: String) -> String {\n \n }\n}"}, {"value": "kotlin", "text": "Kotlin", "defaultCode": "class Solution {\n fun longestPalindrome(s: String): String {\n \n }\n}"}, {"value": "dart", "text": "Dart", "defaultCode": "class Solution {\n String longestPalindrome(String s) {\n \n }\n}"}, {"value": "golang", "text": "Go", "defaultCode": "func longestPalindrome(s string) string {\n \n}"}, {"value": "ruby", "text": "Ruby", "defaultCode": "# @param {String} s\n# @return {String}\ndef longest_palindrome(s)\n \nend"}, {"value": "scala", "text": "Scala", "defaultCode": "object Solution {\n def longestPalindrome(s: String): String = {\n \n }\n}"}, {"value": "rust", "text": "Rust", "defaultCode": "impl Solution {\n pub fn longest_palindrome(s: String) -> String {\n \n }\n}"}, {"value": "racket", "text": "Racket", "defaultCode": "(define/contract (longest-palindrome s)\n (-> string? string?)\n )"}, {"value": "erlang", "text": "Erlang", "defaultCode": "-spec longest_palindrome(S :: unicode:unicode_binary()) -> unicode:unicode_binary().\nlongest_palindrome(S) ->\n ."}, {"value": "elixir", "text": "Elixir", "defaultCode": "defmodule Solution do\n @spec longest_palindrome(s :: String.t) :: String.t\n def longest_palindrome(s) do\n \n end\nend"}] | "babad" | {
"name": "longestPalindrome",
"params": [
{
"name": "s",
"type": "string"
}
],
"return": {
"type": "string"
}
} | {"cpp": ["C++", "<p>Compiled with <code> clang 19 </code> using the latest C++ 23 standard, and <code>libstdc++</code> provided by GCC 14.</p>\r\n\r\n<p>Your code is compiled with level two optimization (<code>-O2</code>). <a href=\"https://github.com/google/sanitizers/wiki/AddressSanitizer\" target=\"_blank\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>"], "java": ["Java", "<p><code>OpenJDK 21</code>. Using compile arguments: <code>--enable-preview --release 21</code></p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>\r\n<p>Includes <code>Pair</code> class from https://docs.oracle.com/javase/8/javafx/api/javafx/util/Pair.html.</p>"], "python": ["Python", "<p><code>Python 2.7.18</code>.</p>\r\n\r\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\"https://docs.python.org/2/library/array.html\" target=\"_blank\">array</a>, <a href=\"https://docs.python.org/2/library/bisect.html\" target=\"_blank\">bisect</a>, <a href=\"https://docs.python.org/2/library/collections.html\" target=\"_blank\">collections</a>. If you need more libraries, you can import it yourself.</p>\r\n\r\n<p>For Map/TreeMap data structure, you may use <a href=\"http://www.grantjenks.com/docs/sortedcontainers/\" target=\"_blank\">sortedcontainers</a> library.</p>\r\n\r\n<p>Note that Python 2.7 <a href=\"https://www.python.org/dev/peps/pep-0373/\" target=\"_blank\">is not maintained anymore</a>. For the latest Python, please choose Python3 instead.</p>"], "c": ["C", "<p>Compiled with <code>gcc 14</code> using the gnu11 standard.</p>\r\n\r\n<p>Your code is compiled with level one optimization (<code>-O2</code>). <a href=\"https://github.com/google/sanitizers/wiki/AddressSanitizer\" target=\"_blank\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>\r\n\r\n<p>For hash table operations, you may use <a href=\"https://troydhanson.github.io/uthash/\" target=\"_blank\">uthash</a>. \"uthash.h\" is included by default. Below are some examples:</p>\r\n\r\n<p><b>1. Adding an item to a hash.</b>\r\n<pre>\r\nstruct hash_entry {\r\n int id; /* we'll use this field as the key */\r\n char name[10];\r\n UT_hash_handle hh; /* makes this structure hashable */\r\n};\r\n\r\nstruct hash_entry *users = NULL;\r\n\r\nvoid add_user(struct hash_entry *s) {\r\n HASH_ADD_INT(users, id, s);\r\n}\r\n</pre>\r\n</p>\r\n\r\n<p><b>2. Looking up an item in a hash:</b>\r\n<pre>\r\nstruct hash_entry *find_user(int user_id) {\r\n struct hash_entry *s;\r\n HASH_FIND_INT(users, &user_id, s);\r\n return s;\r\n}\r\n</pre>\r\n</p>\r\n\r\n<p><b>3. Deleting an item in a hash:</b>\r\n<pre>\r\nvoid delete_user(struct hash_entry *user) {\r\n HASH_DEL(users, user); \r\n}\r\n</pre>\r\n</p>"], "csharp": ["C#", "<p><a href=\"https://learn.microsoft.com/en-us/dotnet/csharp/whats-new/csharp-13\" target=\"_blank\">C# 13</a> with .NET 9 runtime</p>"], "javascript": ["JavaScript", "<p><code>Node.js 22.14.0</code>.</p>\r\n\r\n<p>Your code is run with <code>--harmony</code> flag, enabling <a href=\"http://node.green/\" target=\"_blank\">new ES6 features</a>.</p>\r\n\r\n<p><a href=\"https://lodash.com\" target=\"_blank\">lodash.js</a> library is included by default.</p>\r\n\r\n<p>For Priority Queue / Queue data structures, you may use 6.3.2 version of <a href=\"https://github.com/datastructures-js/priority-queue/tree/v6.3.2\" target=\"_blank\">datastructures-js/priority-queue</a> and 4.2.3 version of <a href=\"https://github.com/datastructures-js/queue/tree/v4.2.3\" target=\"_blank\">datastructures-js/queue</a> and 1.0.4 version of <a href=\"https://github.com/datastructures-js/deque/tree/v1.0.4\" target=\"_blank\">datastructures-js/deque</a>.</p>"], "ruby": ["Ruby", "<p><code>Ruby 3.2</code></p>\r\n\r\n<p>Some common data structure implementations are provided in the Algorithms module: https://www.rubydoc.info/github/kanwei/algorithms/Algorithms</p>"], "swift": ["Swift", "<p><code>Swift 6.0</code>.</p>\r\n\r\n<p>You may use the following packages:<br/>\r\n<a href=\"https://github.com/apple/swift-algorithms/tree/1.2.0\" target=\"_blank\">swift-algorithms 1.2.0</a><br/>\r\n<a href=\"https://github.com/apple/swift-collections/tree/1.1.4\" target=\"_blank\">swift-collections 1.1.4</a><br/>\r\n<a href=\"https://github.com/apple/swift-numerics/tree/1.0.2\" target=\"_blank\">swift-numerics 1.0.2</a></p>"], "golang": ["Go", "<p><code>Go 1.23</code></p>\r\n<p>Support <a href=\"https://pkg.go.dev/github.com/emirpasic/[email protected]\" target=\"_blank\">https://pkg.go.dev/github.com/emirpasic/[email protected]</a> and <a href=\"https://pkg.go.dev/github.com/emirpasic/gods/[email protected]\" target=\"_blank\">https://pkg.go.dev/github.com/emirpasic/gods/[email protected]</a> library.</p>"], "python3": ["Python3", "<p><code>Python 3.11</code>.</p>\r\n\r\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\"https://docs.python.org/3/library/array.html\" target=\"_blank\">array</a>, <a href=\"https://docs.python.org/3/library/bisect.html\" target=\"_blank\">bisect</a>, <a href=\"https://docs.python.org/3/library/collections.html\" target=\"_blank\">collections</a>. If you need more libraries, you can import it yourself.</p>\r\n\r\n<p>For Map/TreeMap data structure, you may use <a href=\"http://www.grantjenks.com/docs/sortedcontainers/\" target=\"_blank\">sortedcontainers</a> library.</p>"], "scala": ["Scala", "<p><code>Scala 3.3.1</code>.</p>"], "kotlin": ["Kotlin", "<p><code>Kotlin 2.1.10</code>.</p>"], "rust": ["Rust", "<p><code>Rust 1.85.0</code>. Your code will be compiled with <code>opt-level</code> 2.</p>\r\n\r\n<p>Supports <a href=\"https://crates.io/crates/rand\" target=\"_blank\">rand v0.8</a> and <a href=\"https://crates.io/crates/regex\" target=\"_blank\">regex\u00a0v1</a> and <a href=\"https://crates.io/crates/itertools\" target=\"_blank\">itertools\u00a0v0.14</a> from crates.io</p>"], "php": ["PHP", "<p><code>PHP 8.2</code>.</p>\r\n<p>With bcmath module</p>"], "typescript": ["Typescript", "<p><code>TypeScript 5.7.3, Node.js 22.14.0</code>.</p>\r\n\r\n<p>Compile Options: <code>--alwaysStrict --strictBindCallApply --strictFunctionTypes --target ES2024</code></p>\r\n\r\n<p><a href=\"https://lodash.com\" target=\"_blank\">lodash.js</a> library is included by default.</p>\r\n\r\n<p>For Priority Queue / Queue data structures, you may use 6.3.2 version of <a href=\"https://github.com/datastructures-js/priority-queue/tree/v6.3.2\" target=\"_blank\">datastructures-js/priority-queue</a> and 4.2.3 version of <a href=\"https://github.com/datastructures-js/queue/tree/v4.2.3\" target=\"_blank\">datastructures-js/queue</a> and 1.0.4 version of <a href=\"https://github.com/datastructures-js/deque/tree/v1.0.4\" target=\"_blank\">datastructures-js/deque</a>.</p>"], "racket": ["Racket", "<p><a href=\"https://docs.racket-lang.org/guide/performance.html#%28tech._c%29\" target=\"_blank\">Racket CS</a> v8.15</p>\r\n\r\n<p>Using <code>#lang racket</code></p>\r\n\r\n<p>Required <code>data/gvector data/queue data/order data/heap</code> automatically for your convenience</p>"], "erlang": ["Erlang", "Erlang/OTP 26"], "elixir": ["Elixir", "Elixir 1.17 with Erlang/OTP 26"], "dart": ["Dart", "<p>Dart 3.2. You may use package <a href=\"https://pub.dev/packages/collection/versions/1.18.0\" target=\"_blank\">collection</a></p>\r\n\r\n<p>Your code will be run directly without compiling</p>"]} | ['Two Pointers', 'String', 'Dynamic Programming'] |
6 | Zigzag Conversion | zigzag-conversion | <p>The string <code>"PAYPALISHIRING"</code> is written in a zigzag pattern on a given number of rows like this: (you may want to display this pattern in a fixed font for better legibility)</p>
<pre>
P A H N
A P L S I I G
Y I R
</pre>
<p>And then read line by line: <code>"PAHNAPLSIIGYIR"</code></p>
<p>Write the code that will take a string and make this conversion given a number of rows:</p>
<pre>
string convert(string s, int numRows);
</pre>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<strong>Input:</strong> s = "PAYPALISHIRING", numRows = 3
<strong>Output:</strong> "PAHNAPLSIIGYIR"
</pre>
<p><strong class="example">Example 2:</strong></p>
<pre>
<strong>Input:</strong> s = "PAYPALISHIRING", numRows = 4
<strong>Output:</strong> "PINALSIGYAHRPI"
<strong>Explanation:</strong>
P I N
A L S I G
Y A H R
P I
</pre>
<p><strong class="example">Example 3:</strong></p>
<pre>
<strong>Input:</strong> s = "A", numRows = 1
<strong>Output:</strong> "A"
</pre>
<p> </p>
<p><strong>Constraints:</strong></p>
<ul>
<li><code>1 <= s.length <= 1000</code></li>
<li><code>s</code> consists of English letters (lower-case and upper-case), <code>','</code> and <code>'.'</code>.</li>
<li><code>1 <= numRows <= 1000</code></li>
</ul>
| Medium | 1.7M | 3.3M | 1,702,325 | 3,332,883 | 51.1% | [] | [] | Algorithms | [{"value": "cpp", "text": "C++", "defaultCode": "class Solution {\npublic:\n string convert(string s, int numRows) {\n \n }\n};"}, {"value": "java", "text": "Java", "defaultCode": "class Solution {\n public String convert(String s, int numRows) {\n \n }\n}"}, {"value": "python", "text": "Python", "defaultCode": "class Solution(object):\n def convert(self, s, numRows):\n \"\"\"\n :type s: str\n :type numRows: int\n :rtype: str\n \"\"\"\n "}, {"value": "python3", "text": "Python3", "defaultCode": "class Solution:\n def convert(self, s: str, numRows: int) -> str:\n "}, {"value": "c", "text": "C", "defaultCode": "char* convert(char* s, int numRows) {\n \n}"}, {"value": "csharp", "text": "C#", "defaultCode": "public class Solution {\n public string Convert(string s, int numRows) {\n \n }\n}"}, {"value": "javascript", "text": "JavaScript", "defaultCode": "/**\n * @param {string} s\n * @param {number} numRows\n * @return {string}\n */\nvar convert = function(s, numRows) {\n \n};"}, {"value": "typescript", "text": "TypeScript", "defaultCode": "function convert(s: string, numRows: number): string {\n \n};"}, {"value": "php", "text": "PHP", "defaultCode": "class Solution {\n\n /**\n * @param String $s\n * @param Integer $numRows\n * @return String\n */\n function convert($s, $numRows) {\n \n }\n}"}, {"value": "swift", "text": "Swift", "defaultCode": "class Solution {\n func convert(_ s: String, _ numRows: Int) -> String {\n \n }\n}"}, {"value": "kotlin", "text": "Kotlin", "defaultCode": "class Solution {\n fun convert(s: String, numRows: Int): String {\n \n }\n}"}, {"value": "dart", "text": "Dart", "defaultCode": "class Solution {\n String convert(String s, int numRows) {\n \n }\n}"}, {"value": "golang", "text": "Go", "defaultCode": "func convert(s string, numRows int) string {\n \n}"}, {"value": "ruby", "text": "Ruby", "defaultCode": "# @param {String} s\n# @param {Integer} num_rows\n# @return {String}\ndef convert(s, num_rows)\n \nend"}, {"value": "scala", "text": "Scala", "defaultCode": "object Solution {\n def convert(s: String, numRows: Int): String = {\n \n }\n}"}, {"value": "rust", "text": "Rust", "defaultCode": "impl Solution {\n pub fn convert(s: String, num_rows: i32) -> String {\n \n }\n}"}, {"value": "racket", "text": "Racket", "defaultCode": "(define/contract (convert s numRows)\n (-> string? exact-integer? string?)\n )"}, {"value": "erlang", "text": "Erlang", "defaultCode": "-spec convert(S :: unicode:unicode_binary(), NumRows :: integer()) -> unicode:unicode_binary().\nconvert(S, NumRows) ->\n ."}, {"value": "elixir", "text": "Elixir", "defaultCode": "defmodule Solution do\n @spec convert(s :: String.t, num_rows :: integer) :: String.t\n def convert(s, num_rows) do\n \n end\nend"}] | "PAYPALISHIRING"
3 | {
"name": "convert",
"params": [
{
"name": "s",
"type": "string"
},
{
"name": "numRows",
"type": "integer"
}
],
"return": {
"type": "string"
}
} | {"cpp": ["C++", "<p>Compiled with <code> clang 19 </code> using the latest C++ 23 standard, and <code>libstdc++</code> provided by GCC 14.</p>\r\n\r\n<p>Your code is compiled with level two optimization (<code>-O2</code>). <a href=\"https://github.com/google/sanitizers/wiki/AddressSanitizer\" target=\"_blank\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>"], "java": ["Java", "<p><code>OpenJDK 21</code>. Using compile arguments: <code>--enable-preview --release 21</code></p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>\r\n<p>Includes <code>Pair</code> class from https://docs.oracle.com/javase/8/javafx/api/javafx/util/Pair.html.</p>"], "python": ["Python", "<p><code>Python 2.7.18</code>.</p>\r\n\r\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\"https://docs.python.org/2/library/array.html\" target=\"_blank\">array</a>, <a href=\"https://docs.python.org/2/library/bisect.html\" target=\"_blank\">bisect</a>, <a href=\"https://docs.python.org/2/library/collections.html\" target=\"_blank\">collections</a>. If you need more libraries, you can import it yourself.</p>\r\n\r\n<p>For Map/TreeMap data structure, you may use <a href=\"http://www.grantjenks.com/docs/sortedcontainers/\" target=\"_blank\">sortedcontainers</a> library.</p>\r\n\r\n<p>Note that Python 2.7 <a href=\"https://www.python.org/dev/peps/pep-0373/\" target=\"_blank\">is not maintained anymore</a>. For the latest Python, please choose Python3 instead.</p>"], "c": ["C", "<p>Compiled with <code>gcc 14</code> using the gnu11 standard.</p>\r\n\r\n<p>Your code is compiled with level one optimization (<code>-O2</code>). <a href=\"https://github.com/google/sanitizers/wiki/AddressSanitizer\" target=\"_blank\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>\r\n\r\n<p>For hash table operations, you may use <a href=\"https://troydhanson.github.io/uthash/\" target=\"_blank\">uthash</a>. \"uthash.h\" is included by default. Below are some examples:</p>\r\n\r\n<p><b>1. Adding an item to a hash.</b>\r\n<pre>\r\nstruct hash_entry {\r\n int id; /* we'll use this field as the key */\r\n char name[10];\r\n UT_hash_handle hh; /* makes this structure hashable */\r\n};\r\n\r\nstruct hash_entry *users = NULL;\r\n\r\nvoid add_user(struct hash_entry *s) {\r\n HASH_ADD_INT(users, id, s);\r\n}\r\n</pre>\r\n</p>\r\n\r\n<p><b>2. Looking up an item in a hash:</b>\r\n<pre>\r\nstruct hash_entry *find_user(int user_id) {\r\n struct hash_entry *s;\r\n HASH_FIND_INT(users, &user_id, s);\r\n return s;\r\n}\r\n</pre>\r\n</p>\r\n\r\n<p><b>3. Deleting an item in a hash:</b>\r\n<pre>\r\nvoid delete_user(struct hash_entry *user) {\r\n HASH_DEL(users, user); \r\n}\r\n</pre>\r\n</p>"], "csharp": ["C#", "<p><a href=\"https://learn.microsoft.com/en-us/dotnet/csharp/whats-new/csharp-13\" target=\"_blank\">C# 13</a> with .NET 9 runtime</p>"], "javascript": ["JavaScript", "<p><code>Node.js 22.14.0</code>.</p>\r\n\r\n<p>Your code is run with <code>--harmony</code> flag, enabling <a href=\"http://node.green/\" target=\"_blank\">new ES6 features</a>.</p>\r\n\r\n<p><a href=\"https://lodash.com\" target=\"_blank\">lodash.js</a> library is included by default.</p>\r\n\r\n<p>For Priority Queue / Queue data structures, you may use 6.3.2 version of <a href=\"https://github.com/datastructures-js/priority-queue/tree/v6.3.2\" target=\"_blank\">datastructures-js/priority-queue</a> and 4.2.3 version of <a href=\"https://github.com/datastructures-js/queue/tree/v4.2.3\" target=\"_blank\">datastructures-js/queue</a> and 1.0.4 version of <a href=\"https://github.com/datastructures-js/deque/tree/v1.0.4\" target=\"_blank\">datastructures-js/deque</a>.</p>"], "ruby": ["Ruby", "<p><code>Ruby 3.2</code></p>\r\n\r\n<p>Some common data structure implementations are provided in the Algorithms module: https://www.rubydoc.info/github/kanwei/algorithms/Algorithms</p>"], "swift": ["Swift", "<p><code>Swift 6.0</code>.</p>\r\n\r\n<p>You may use the following packages:<br/>\r\n<a href=\"https://github.com/apple/swift-algorithms/tree/1.2.0\" target=\"_blank\">swift-algorithms 1.2.0</a><br/>\r\n<a href=\"https://github.com/apple/swift-collections/tree/1.1.4\" target=\"_blank\">swift-collections 1.1.4</a><br/>\r\n<a href=\"https://github.com/apple/swift-numerics/tree/1.0.2\" target=\"_blank\">swift-numerics 1.0.2</a></p>"], "golang": ["Go", "<p><code>Go 1.23</code></p>\r\n<p>Support <a href=\"https://pkg.go.dev/github.com/emirpasic/[email protected]\" target=\"_blank\">https://pkg.go.dev/github.com/emirpasic/[email protected]</a> and <a href=\"https://pkg.go.dev/github.com/emirpasic/gods/[email protected]\" target=\"_blank\">https://pkg.go.dev/github.com/emirpasic/gods/[email protected]</a> library.</p>"], "python3": ["Python3", "<p><code>Python 3.11</code>.</p>\r\n\r\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\"https://docs.python.org/3/library/array.html\" target=\"_blank\">array</a>, <a href=\"https://docs.python.org/3/library/bisect.html\" target=\"_blank\">bisect</a>, <a href=\"https://docs.python.org/3/library/collections.html\" target=\"_blank\">collections</a>. If you need more libraries, you can import it yourself.</p>\r\n\r\n<p>For Map/TreeMap data structure, you may use <a href=\"http://www.grantjenks.com/docs/sortedcontainers/\" target=\"_blank\">sortedcontainers</a> library.</p>"], "scala": ["Scala", "<p><code>Scala 3.3.1</code>.</p>"], "kotlin": ["Kotlin", "<p><code>Kotlin 2.1.10</code>.</p>"], "rust": ["Rust", "<p><code>Rust 1.85.0</code>. Your code will be compiled with <code>opt-level</code> 2.</p>\r\n\r\n<p>Supports <a href=\"https://crates.io/crates/rand\" target=\"_blank\">rand v0.8</a> and <a href=\"https://crates.io/crates/regex\" target=\"_blank\">regex\u00a0v1</a> and <a href=\"https://crates.io/crates/itertools\" target=\"_blank\">itertools\u00a0v0.14</a> from crates.io</p>"], "php": ["PHP", "<p><code>PHP 8.2</code>.</p>\r\n<p>With bcmath module</p>"], "typescript": ["Typescript", "<p><code>TypeScript 5.7.3, Node.js 22.14.0</code>.</p>\r\n\r\n<p>Compile Options: <code>--alwaysStrict --strictBindCallApply --strictFunctionTypes --target ES2024</code></p>\r\n\r\n<p><a href=\"https://lodash.com\" target=\"_blank\">lodash.js</a> library is included by default.</p>\r\n\r\n<p>For Priority Queue / Queue data structures, you may use 6.3.2 version of <a href=\"https://github.com/datastructures-js/priority-queue/tree/v6.3.2\" target=\"_blank\">datastructures-js/priority-queue</a> and 4.2.3 version of <a href=\"https://github.com/datastructures-js/queue/tree/v4.2.3\" target=\"_blank\">datastructures-js/queue</a> and 1.0.4 version of <a href=\"https://github.com/datastructures-js/deque/tree/v1.0.4\" target=\"_blank\">datastructures-js/deque</a>.</p>"], "racket": ["Racket", "<p><a href=\"https://docs.racket-lang.org/guide/performance.html#%28tech._c%29\" target=\"_blank\">Racket CS</a> v8.15</p>\r\n\r\n<p>Using <code>#lang racket</code></p>\r\n\r\n<p>Required <code>data/gvector data/queue data/order data/heap</code> automatically for your convenience</p>"], "erlang": ["Erlang", "Erlang/OTP 26"], "elixir": ["Elixir", "Elixir 1.17 with Erlang/OTP 26"], "dart": ["Dart", "<p>Dart 3.2. You may use package <a href=\"https://pub.dev/packages/collection/versions/1.18.0\" target=\"_blank\">collection</a></p>\r\n\r\n<p>Your code will be run directly without compiling</p>"]} | ['String'] |
7 | Reverse Integer | reverse-integer | <p>Given a signed 32-bit integer <code>x</code>, return <code>x</code><em> with its digits reversed</em>. If reversing <code>x</code> causes the value to go outside the signed 32-bit integer range <code>[-2<sup>31</sup>, 2<sup>31</sup> - 1]</code>, then return <code>0</code>.</p>
<p><strong>Assume the environment does not allow you to store 64-bit integers (signed or unsigned).</strong></p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<strong>Input:</strong> x = 123
<strong>Output:</strong> 321
</pre>
<p><strong class="example">Example 2:</strong></p>
<pre>
<strong>Input:</strong> x = -123
<strong>Output:</strong> -321
</pre>
<p><strong class="example">Example 3:</strong></p>
<pre>
<strong>Input:</strong> x = 120
<strong>Output:</strong> 21
</pre>
<p> </p>
<p><strong>Constraints:</strong></p>
<ul>
<li><code>-2<sup>31</sup> <= x <= 2<sup>31</sup> - 1</code></li>
</ul>
| Medium | 4M | 13.2M | 3,951,399 | 13,166,975 | 30.0% | ['string-to-integer-atoi', 'reverse-bits', 'a-number-after-a-double-reversal', 'count-number-of-distinct-integers-after-reverse-operations'] | [] | Algorithms | [{"value": "cpp", "text": "C++", "defaultCode": "class Solution {\npublic:\n int reverse(int x) {\n \n }\n};"}, {"value": "java", "text": "Java", "defaultCode": "class Solution {\n public int reverse(int x) {\n \n }\n}"}, {"value": "python", "text": "Python", "defaultCode": "class Solution(object):\n def reverse(self, x):\n \"\"\"\n :type x: int\n :rtype: int\n \"\"\"\n "}, {"value": "python3", "text": "Python3", "defaultCode": "class Solution:\n def reverse(self, x: int) -> int:\n "}, {"value": "c", "text": "C", "defaultCode": "int reverse(int x){\n\n}"}, {"value": "csharp", "text": "C#", "defaultCode": "public class Solution {\n public int Reverse(int x) {\n \n }\n}"}, {"value": "javascript", "text": "JavaScript", "defaultCode": "/**\n * @param {number} x\n * @return {number}\n */\nvar reverse = function(x) {\n \n};"}, {"value": "typescript", "text": "TypeScript", "defaultCode": "function reverse(x: number): number {\n\n};"}, {"value": "php", "text": "PHP", "defaultCode": "class Solution {\n\n /**\n * @param Integer $x\n * @return Integer\n */\n function reverse($x) {\n \n }\n}"}, {"value": "swift", "text": "Swift", "defaultCode": "class Solution {\n func reverse(_ x: Int) -> Int {\n \n }\n}"}, {"value": "kotlin", "text": "Kotlin", "defaultCode": "class Solution {\n fun reverse(x: Int): Int {\n \n }\n}"}, {"value": "dart", "text": "Dart", "defaultCode": "class Solution {\n int reverse(int x) {\n\n }\n}"}, {"value": "golang", "text": "Go", "defaultCode": "func reverse(x int) int {\n \n}"}, {"value": "ruby", "text": "Ruby", "defaultCode": "# @param {Integer} x\n# @return {Integer}\ndef reverse(x)\n \nend"}, {"value": "scala", "text": "Scala", "defaultCode": "object Solution {\n def reverse(x: Int): Int = {\n \n }\n}"}, {"value": "rust", "text": "Rust", "defaultCode": "impl Solution {\n pub fn reverse(x: i32) -> i32 {\n \n }\n}"}, {"value": "racket", "text": "Racket", "defaultCode": "(define/contract (reverse x)\n (-> exact-integer? exact-integer?)\n\n )"}, {"value": "erlang", "text": "Erlang", "defaultCode": "-spec reverse(X :: integer()) -> integer().\nreverse(X) ->\n ."}, {"value": "elixir", "text": "Elixir", "defaultCode": "defmodule Solution do\n @spec reverse(x :: integer) :: integer\n def reverse(x) do\n\n end\nend"}] | 123 | {
"name": "reverse",
"params": [
{
"name": "x",
"type": "integer"
}
],
"return": {
"type": "integer"
}
} | {"cpp": ["C++", "<p>Compiled with <code> clang 19 </code> using the latest C++ 23 standard, and <code>libstdc++</code> provided by GCC 14.</p>\r\n\r\n<p>Your code is compiled with level two optimization (<code>-O2</code>). <a href=\"https://github.com/google/sanitizers/wiki/AddressSanitizer\" target=\"_blank\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>"], "java": ["Java", "<p><code>OpenJDK 21</code>. Using compile arguments: <code>--enable-preview --release 21</code></p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>\r\n<p>Includes <code>Pair</code> class from https://docs.oracle.com/javase/8/javafx/api/javafx/util/Pair.html.</p>"], "python": ["Python", "<p><code>Python 2.7.18</code>.</p>\r\n\r\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\"https://docs.python.org/2/library/array.html\" target=\"_blank\">array</a>, <a href=\"https://docs.python.org/2/library/bisect.html\" target=\"_blank\">bisect</a>, <a href=\"https://docs.python.org/2/library/collections.html\" target=\"_blank\">collections</a>. If you need more libraries, you can import it yourself.</p>\r\n\r\n<p>For Map/TreeMap data structure, you may use <a href=\"http://www.grantjenks.com/docs/sortedcontainers/\" target=\"_blank\">sortedcontainers</a> library.</p>\r\n\r\n<p>Note that Python 2.7 <a href=\"https://www.python.org/dev/peps/pep-0373/\" target=\"_blank\">is not maintained anymore</a>. For the latest Python, please choose Python3 instead.</p>"], "c": ["C", "<p>Compiled with <code>gcc 14</code> using the gnu11 standard.</p>\r\n\r\n<p>Your code is compiled with level one optimization (<code>-O2</code>). <a href=\"https://github.com/google/sanitizers/wiki/AddressSanitizer\" target=\"_blank\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>\r\n\r\n<p>For hash table operations, you may use <a href=\"https://troydhanson.github.io/uthash/\" target=\"_blank\">uthash</a>. \"uthash.h\" is included by default. Below are some examples:</p>\r\n\r\n<p><b>1. Adding an item to a hash.</b>\r\n<pre>\r\nstruct hash_entry {\r\n int id; /* we'll use this field as the key */\r\n char name[10];\r\n UT_hash_handle hh; /* makes this structure hashable */\r\n};\r\n\r\nstruct hash_entry *users = NULL;\r\n\r\nvoid add_user(struct hash_entry *s) {\r\n HASH_ADD_INT(users, id, s);\r\n}\r\n</pre>\r\n</p>\r\n\r\n<p><b>2. Looking up an item in a hash:</b>\r\n<pre>\r\nstruct hash_entry *find_user(int user_id) {\r\n struct hash_entry *s;\r\n HASH_FIND_INT(users, &user_id, s);\r\n return s;\r\n}\r\n</pre>\r\n</p>\r\n\r\n<p><b>3. Deleting an item in a hash:</b>\r\n<pre>\r\nvoid delete_user(struct hash_entry *user) {\r\n HASH_DEL(users, user); \r\n}\r\n</pre>\r\n</p>"], "csharp": ["C#", "<p><a href=\"https://learn.microsoft.com/en-us/dotnet/csharp/whats-new/csharp-13\" target=\"_blank\">C# 13</a> with .NET 9 runtime</p>"], "javascript": ["JavaScript", "<p><code>Node.js 22.14.0</code>.</p>\r\n\r\n<p>Your code is run with <code>--harmony</code> flag, enabling <a href=\"http://node.green/\" target=\"_blank\">new ES6 features</a>.</p>\r\n\r\n<p><a href=\"https://lodash.com\" target=\"_blank\">lodash.js</a> library is included by default.</p>\r\n\r\n<p>For Priority Queue / Queue data structures, you may use 6.3.2 version of <a href=\"https://github.com/datastructures-js/priority-queue/tree/v6.3.2\" target=\"_blank\">datastructures-js/priority-queue</a> and 4.2.3 version of <a href=\"https://github.com/datastructures-js/queue/tree/v4.2.3\" target=\"_blank\">datastructures-js/queue</a> and 1.0.4 version of <a href=\"https://github.com/datastructures-js/deque/tree/v1.0.4\" target=\"_blank\">datastructures-js/deque</a>.</p>"], "ruby": ["Ruby", "<p><code>Ruby 3.2</code></p>\r\n\r\n<p>Some common data structure implementations are provided in the Algorithms module: https://www.rubydoc.info/github/kanwei/algorithms/Algorithms</p>"], "swift": ["Swift", "<p><code>Swift 6.0</code>.</p>\r\n\r\n<p>You may use the following packages:<br/>\r\n<a href=\"https://github.com/apple/swift-algorithms/tree/1.2.0\" target=\"_blank\">swift-algorithms 1.2.0</a><br/>\r\n<a href=\"https://github.com/apple/swift-collections/tree/1.1.4\" target=\"_blank\">swift-collections 1.1.4</a><br/>\r\n<a href=\"https://github.com/apple/swift-numerics/tree/1.0.2\" target=\"_blank\">swift-numerics 1.0.2</a></p>"], "golang": ["Go", "<p><code>Go 1.23</code></p>\r\n<p>Support <a href=\"https://pkg.go.dev/github.com/emirpasic/[email protected]\" target=\"_blank\">https://pkg.go.dev/github.com/emirpasic/[email protected]</a> and <a href=\"https://pkg.go.dev/github.com/emirpasic/gods/[email protected]\" target=\"_blank\">https://pkg.go.dev/github.com/emirpasic/gods/[email protected]</a> library.</p>"], "python3": ["Python3", "<p><code>Python 3.11</code>.</p>\r\n\r\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\"https://docs.python.org/3/library/array.html\" target=\"_blank\">array</a>, <a href=\"https://docs.python.org/3/library/bisect.html\" target=\"_blank\">bisect</a>, <a href=\"https://docs.python.org/3/library/collections.html\" target=\"_blank\">collections</a>. If you need more libraries, you can import it yourself.</p>\r\n\r\n<p>For Map/TreeMap data structure, you may use <a href=\"http://www.grantjenks.com/docs/sortedcontainers/\" target=\"_blank\">sortedcontainers</a> library.</p>"], "scala": ["Scala", "<p><code>Scala 3.3.1</code>.</p>"], "kotlin": ["Kotlin", "<p><code>Kotlin 2.1.10</code>.</p>"], "rust": ["Rust", "<p><code>Rust 1.85.0</code>. Your code will be compiled with <code>opt-level</code> 2.</p>\r\n\r\n<p>Supports <a href=\"https://crates.io/crates/rand\" target=\"_blank\">rand v0.8</a> and <a href=\"https://crates.io/crates/regex\" target=\"_blank\">regex\u00a0v1</a> and <a href=\"https://crates.io/crates/itertools\" target=\"_blank\">itertools\u00a0v0.14</a> from crates.io</p>"], "php": ["PHP", "<p><code>PHP 8.2</code>.</p>\r\n<p>With bcmath module</p>"], "typescript": ["Typescript", "<p><code>TypeScript 5.7.3, Node.js 22.14.0</code>.</p>\r\n\r\n<p>Compile Options: <code>--alwaysStrict --strictBindCallApply --strictFunctionTypes --target ES2024</code></p>\r\n\r\n<p><a href=\"https://lodash.com\" target=\"_blank\">lodash.js</a> library is included by default.</p>\r\n\r\n<p>For Priority Queue / Queue data structures, you may use 6.3.2 version of <a href=\"https://github.com/datastructures-js/priority-queue/tree/v6.3.2\" target=\"_blank\">datastructures-js/priority-queue</a> and 4.2.3 version of <a href=\"https://github.com/datastructures-js/queue/tree/v4.2.3\" target=\"_blank\">datastructures-js/queue</a> and 1.0.4 version of <a href=\"https://github.com/datastructures-js/deque/tree/v1.0.4\" target=\"_blank\">datastructures-js/deque</a>.</p>"], "racket": ["Racket", "<p><a href=\"https://docs.racket-lang.org/guide/performance.html#%28tech._c%29\" target=\"_blank\">Racket CS</a> v8.15</p>\r\n\r\n<p>Using <code>#lang racket</code></p>\r\n\r\n<p>Required <code>data/gvector data/queue data/order data/heap</code> automatically for your convenience</p>"], "erlang": ["Erlang", "Erlang/OTP 26"], "elixir": ["Elixir", "Elixir 1.17 with Erlang/OTP 26"], "dart": ["Dart", "<p>Dart 3.2. You may use package <a href=\"https://pub.dev/packages/collection/versions/1.18.0\" target=\"_blank\">collection</a></p>\r\n\r\n<p>Your code will be run directly without compiling</p>"]} | ['Math'] |
8 | String to Integer (atoi) | string-to-integer-atoi | <p>Implement the <code>myAtoi(string s)</code> function, which converts a string to a 32-bit signed integer.</p>
<p>The algorithm for <code>myAtoi(string s)</code> is as follows:</p>
<ol>
<li><strong>Whitespace</strong>: Ignore any leading whitespace (<code>" "</code>).</li>
<li><strong>Signedness</strong>: Determine the sign by checking if the next character is <code>'-'</code> or <code>'+'</code>, assuming positivity if neither present.</li>
<li><strong>Conversion</strong>: Read the integer by skipping leading zeros until a non-digit character is encountered or the end of the string is reached. If no digits were read, then the result is 0.</li>
<li><strong>Rounding</strong>: If the integer is out of the 32-bit signed integer range <code>[-2<sup>31</sup>, 2<sup>31</sup> - 1]</code>, then round the integer to remain in the range. Specifically, integers less than <code>-2<sup>31</sup></code> should be rounded to <code>-2<sup>31</sup></code>, and integers greater than <code>2<sup>31</sup> - 1</code> should be rounded to <code>2<sup>31</sup> - 1</code>.</li>
</ol>
<p>Return the integer as the final result.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<div class="example-block">
<p><strong>Input:</strong> <span class="example-io">s = "42"</span></p>
<p><strong>Output:</strong> <span class="example-io">42</span></p>
<p><strong>Explanation:</strong></p>
<pre>
The underlined characters are what is read in and the caret is the current reader position.
Step 1: "42" (no characters read because there is no leading whitespace)
^
Step 2: "42" (no characters read because there is neither a '-' nor '+')
^
Step 3: "<u>42</u>" ("42" is read in)
^
</pre>
</div>
<p><strong class="example">Example 2:</strong></p>
<div class="example-block">
<p><strong>Input:</strong> <span class="example-io">s = " -042"</span></p>
<p><strong>Output:</strong> <span class="example-io">-42</span></p>
<p><strong>Explanation:</strong></p>
<pre>
Step 1: "<u> </u>-042" (leading whitespace is read and ignored)
^
Step 2: " <u>-</u>042" ('-' is read, so the result should be negative)
^
Step 3: " -<u>042</u>" ("042" is read in, leading zeros ignored in the result)
^
</pre>
</div>
<p><strong class="example">Example 3:</strong></p>
<div class="example-block">
<p><strong>Input:</strong> <span class="example-io">s = "1337c0d3"</span></p>
<p><strong>Output:</strong> <span class="example-io">1337</span></p>
<p><strong>Explanation:</strong></p>
<pre>
Step 1: "1337c0d3" (no characters read because there is no leading whitespace)
^
Step 2: "1337c0d3" (no characters read because there is neither a '-' nor '+')
^
Step 3: "<u>1337</u>c0d3" ("1337" is read in; reading stops because the next character is a non-digit)
^
</pre>
</div>
<p><strong class="example">Example 4:</strong></p>
<div class="example-block">
<p><strong>Input:</strong> <span class="example-io">s = "0-1"</span></p>
<p><strong>Output:</strong> <span class="example-io">0</span></p>
<p><strong>Explanation:</strong></p>
<pre>
Step 1: "0-1" (no characters read because there is no leading whitespace)
^
Step 2: "0-1" (no characters read because there is neither a '-' nor '+')
^
Step 3: "<u>0</u>-1" ("0" is read in; reading stops because the next character is a non-digit)
^
</pre>
</div>
<p><strong class="example">Example 5:</strong></p>
<div class="example-block">
<p><strong>Input:</strong> <span class="example-io">s = "words and 987"</span></p>
<p><strong>Output:</strong> <span class="example-io">0</span></p>
<p><strong>Explanation:</strong></p>
<p>Reading stops at the first non-digit character 'w'.</p>
</div>
<p> </p>
<p><strong>Constraints:</strong></p>
<ul>
<li><code>0 <= s.length <= 200</code></li>
<li><code>s</code> consists of English letters (lower-case and upper-case), digits (<code>0-9</code>), <code>' '</code>, <code>'+'</code>, <code>'-'</code>, and <code>'.'</code>.</li>
</ul>
| Medium | 1.9M | 10.1M | 1,913,260 | 10,125,663 | 18.9% | ['reverse-integer', 'valid-number', 'check-if-numbers-are-ascending-in-a-sentence'] | [] | Algorithms | [{"value": "cpp", "text": "C++", "defaultCode": "class Solution {\npublic:\n int myAtoi(string s) {\n \n }\n};"}, {"value": "java", "text": "Java", "defaultCode": "class Solution {\n public int myAtoi(String s) {\n \n }\n}"}, {"value": "python", "text": "Python", "defaultCode": "class Solution(object):\n def myAtoi(self, s):\n \"\"\"\n :type s: str\n :rtype: int\n \"\"\"\n "}, {"value": "python3", "text": "Python3", "defaultCode": "class Solution:\n def myAtoi(self, s: str) -> int:\n "}, {"value": "c", "text": "C", "defaultCode": "int myAtoi(char* s) {\n \n}"}, {"value": "csharp", "text": "C#", "defaultCode": "public class Solution {\n public int MyAtoi(string s) {\n \n }\n}"}, {"value": "javascript", "text": "JavaScript", "defaultCode": "/**\n * @param {string} s\n * @return {number}\n */\nvar myAtoi = function(s) {\n \n};"}, {"value": "typescript", "text": "TypeScript", "defaultCode": "function myAtoi(s: string): number {\n \n};"}, {"value": "php", "text": "PHP", "defaultCode": "class Solution {\n\n /**\n * @param String $s\n * @return Integer\n */\n function myAtoi($s) {\n \n }\n}"}, {"value": "swift", "text": "Swift", "defaultCode": "class Solution {\n func myAtoi(_ s: String) -> Int {\n \n }\n}"}, {"value": "kotlin", "text": "Kotlin", "defaultCode": "class Solution {\n fun myAtoi(s: String): Int {\n \n }\n}"}, {"value": "dart", "text": "Dart", "defaultCode": "class Solution {\n int myAtoi(String s) {\n \n }\n}"}, {"value": "golang", "text": "Go", "defaultCode": "func myAtoi(s string) int {\n \n}"}, {"value": "ruby", "text": "Ruby", "defaultCode": "# @param {String} s\n# @return {Integer}\ndef my_atoi(s)\n \nend"}, {"value": "scala", "text": "Scala", "defaultCode": "object Solution {\n def myAtoi(s: String): Int = {\n \n }\n}"}, {"value": "rust", "text": "Rust", "defaultCode": "impl Solution {\n pub fn my_atoi(s: String) -> i32 {\n \n }\n}"}, {"value": "racket", "text": "Racket", "defaultCode": "(define/contract (my-atoi s)\n (-> string? exact-integer?)\n )"}, {"value": "erlang", "text": "Erlang", "defaultCode": "-spec my_atoi(S :: unicode:unicode_binary()) -> integer().\nmy_atoi(S) ->\n ."}, {"value": "elixir", "text": "Elixir", "defaultCode": "defmodule Solution do\n @spec my_atoi(s :: String.t) :: integer\n def my_atoi(s) do\n \n end\nend"}] | "42" | {
"name": "myAtoi",
"params": [
{
"name": "s",
"type": "string"
}
],
"return": {
"type": "integer"
}
} | {"cpp": ["C++", "<p>Compiled with <code> clang 19 </code> using the latest C++ 23 standard, and <code>libstdc++</code> provided by GCC 14.</p>\r\n\r\n<p>Your code is compiled with level two optimization (<code>-O2</code>). <a href=\"https://github.com/google/sanitizers/wiki/AddressSanitizer\" target=\"_blank\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>"], "java": ["Java", "<p><code>OpenJDK 21</code>. Using compile arguments: <code>--enable-preview --release 21</code></p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>\r\n<p>Includes <code>Pair</code> class from https://docs.oracle.com/javase/8/javafx/api/javafx/util/Pair.html.</p>"], "python": ["Python", "<p><code>Python 2.7.18</code>.</p>\r\n\r\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\"https://docs.python.org/2/library/array.html\" target=\"_blank\">array</a>, <a href=\"https://docs.python.org/2/library/bisect.html\" target=\"_blank\">bisect</a>, <a href=\"https://docs.python.org/2/library/collections.html\" target=\"_blank\">collections</a>. If you need more libraries, you can import it yourself.</p>\r\n\r\n<p>For Map/TreeMap data structure, you may use <a href=\"http://www.grantjenks.com/docs/sortedcontainers/\" target=\"_blank\">sortedcontainers</a> library.</p>\r\n\r\n<p>Note that Python 2.7 <a href=\"https://www.python.org/dev/peps/pep-0373/\" target=\"_blank\">is not maintained anymore</a>. For the latest Python, please choose Python3 instead.</p>"], "c": ["C", "<p>Compiled with <code>gcc 14</code> using the gnu11 standard.</p>\r\n\r\n<p>Your code is compiled with level one optimization (<code>-O2</code>). <a href=\"https://github.com/google/sanitizers/wiki/AddressSanitizer\" target=\"_blank\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>\r\n\r\n<p>For hash table operations, you may use <a href=\"https://troydhanson.github.io/uthash/\" target=\"_blank\">uthash</a>. \"uthash.h\" is included by default. Below are some examples:</p>\r\n\r\n<p><b>1. Adding an item to a hash.</b>\r\n<pre>\r\nstruct hash_entry {\r\n int id; /* we'll use this field as the key */\r\n char name[10];\r\n UT_hash_handle hh; /* makes this structure hashable */\r\n};\r\n\r\nstruct hash_entry *users = NULL;\r\n\r\nvoid add_user(struct hash_entry *s) {\r\n HASH_ADD_INT(users, id, s);\r\n}\r\n</pre>\r\n</p>\r\n\r\n<p><b>2. Looking up an item in a hash:</b>\r\n<pre>\r\nstruct hash_entry *find_user(int user_id) {\r\n struct hash_entry *s;\r\n HASH_FIND_INT(users, &user_id, s);\r\n return s;\r\n}\r\n</pre>\r\n</p>\r\n\r\n<p><b>3. Deleting an item in a hash:</b>\r\n<pre>\r\nvoid delete_user(struct hash_entry *user) {\r\n HASH_DEL(users, user); \r\n}\r\n</pre>\r\n</p>"], "csharp": ["C#", "<p><a href=\"https://learn.microsoft.com/en-us/dotnet/csharp/whats-new/csharp-13\" target=\"_blank\">C# 13</a> with .NET 9 runtime</p>"], "javascript": ["JavaScript", "<p><code>Node.js 22.14.0</code>.</p>\r\n\r\n<p>Your code is run with <code>--harmony</code> flag, enabling <a href=\"http://node.green/\" target=\"_blank\">new ES6 features</a>.</p>\r\n\r\n<p><a href=\"https://lodash.com\" target=\"_blank\">lodash.js</a> library is included by default.</p>\r\n\r\n<p>For Priority Queue / Queue data structures, you may use 6.3.2 version of <a href=\"https://github.com/datastructures-js/priority-queue/tree/v6.3.2\" target=\"_blank\">datastructures-js/priority-queue</a> and 4.2.3 version of <a href=\"https://github.com/datastructures-js/queue/tree/v4.2.3\" target=\"_blank\">datastructures-js/queue</a> and 1.0.4 version of <a href=\"https://github.com/datastructures-js/deque/tree/v1.0.4\" target=\"_blank\">datastructures-js/deque</a>.</p>"], "ruby": ["Ruby", "<p><code>Ruby 3.2</code></p>\r\n\r\n<p>Some common data structure implementations are provided in the Algorithms module: https://www.rubydoc.info/github/kanwei/algorithms/Algorithms</p>"], "swift": ["Swift", "<p><code>Swift 6.0</code>.</p>\r\n\r\n<p>You may use the following packages:<br/>\r\n<a href=\"https://github.com/apple/swift-algorithms/tree/1.2.0\" target=\"_blank\">swift-algorithms 1.2.0</a><br/>\r\n<a href=\"https://github.com/apple/swift-collections/tree/1.1.4\" target=\"_blank\">swift-collections 1.1.4</a><br/>\r\n<a href=\"https://github.com/apple/swift-numerics/tree/1.0.2\" target=\"_blank\">swift-numerics 1.0.2</a></p>"], "golang": ["Go", "<p><code>Go 1.23</code></p>\r\n<p>Support <a href=\"https://pkg.go.dev/github.com/emirpasic/[email protected]\" target=\"_blank\">https://pkg.go.dev/github.com/emirpasic/[email protected]</a> and <a href=\"https://pkg.go.dev/github.com/emirpasic/gods/[email protected]\" target=\"_blank\">https://pkg.go.dev/github.com/emirpasic/gods/[email protected]</a> library.</p>"], "python3": ["Python3", "<p><code>Python 3.11</code>.</p>\r\n\r\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\"https://docs.python.org/3/library/array.html\" target=\"_blank\">array</a>, <a href=\"https://docs.python.org/3/library/bisect.html\" target=\"_blank\">bisect</a>, <a href=\"https://docs.python.org/3/library/collections.html\" target=\"_blank\">collections</a>. If you need more libraries, you can import it yourself.</p>\r\n\r\n<p>For Map/TreeMap data structure, you may use <a href=\"http://www.grantjenks.com/docs/sortedcontainers/\" target=\"_blank\">sortedcontainers</a> library.</p>"], "scala": ["Scala", "<p><code>Scala 3.3.1</code>.</p>"], "kotlin": ["Kotlin", "<p><code>Kotlin 2.1.10</code>.</p>"], "rust": ["Rust", "<p><code>Rust 1.85.0</code>. Your code will be compiled with <code>opt-level</code> 2.</p>\r\n\r\n<p>Supports <a href=\"https://crates.io/crates/rand\" target=\"_blank\">rand v0.8</a> and <a href=\"https://crates.io/crates/regex\" target=\"_blank\">regex\u00a0v1</a> and <a href=\"https://crates.io/crates/itertools\" target=\"_blank\">itertools\u00a0v0.14</a> from crates.io</p>"], "php": ["PHP", "<p><code>PHP 8.2</code>.</p>\r\n<p>With bcmath module</p>"], "typescript": ["Typescript", "<p><code>TypeScript 5.7.3, Node.js 22.14.0</code>.</p>\r\n\r\n<p>Compile Options: <code>--alwaysStrict --strictBindCallApply --strictFunctionTypes --target ES2024</code></p>\r\n\r\n<p><a href=\"https://lodash.com\" target=\"_blank\">lodash.js</a> library is included by default.</p>\r\n\r\n<p>For Priority Queue / Queue data structures, you may use 6.3.2 version of <a href=\"https://github.com/datastructures-js/priority-queue/tree/v6.3.2\" target=\"_blank\">datastructures-js/priority-queue</a> and 4.2.3 version of <a href=\"https://github.com/datastructures-js/queue/tree/v4.2.3\" target=\"_blank\">datastructures-js/queue</a> and 1.0.4 version of <a href=\"https://github.com/datastructures-js/deque/tree/v1.0.4\" target=\"_blank\">datastructures-js/deque</a>.</p>"], "racket": ["Racket", "<p><a href=\"https://docs.racket-lang.org/guide/performance.html#%28tech._c%29\" target=\"_blank\">Racket CS</a> v8.15</p>\r\n\r\n<p>Using <code>#lang racket</code></p>\r\n\r\n<p>Required <code>data/gvector data/queue data/order data/heap</code> automatically for your convenience</p>"], "erlang": ["Erlang", "Erlang/OTP 26"], "elixir": ["Elixir", "Elixir 1.17 with Erlang/OTP 26"], "dart": ["Dart", "<p>Dart 3.2. You may use package <a href=\"https://pub.dev/packages/collection/versions/1.18.0\" target=\"_blank\">collection</a></p>\r\n\r\n<p>Your code will be run directly without compiling</p>"]} | ['String'] |
9 | Palindrome Number | palindrome-number | <p>Given an integer <code>x</code>, return <code>true</code><em> if </em><code>x</code><em> is a </em><span data-keyword="palindrome-integer"><em><strong>palindrome</strong></em></span><em>, and </em><code>false</code><em> otherwise</em>.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<strong>Input:</strong> x = 121
<strong>Output:</strong> true
<strong>Explanation:</strong> 121 reads as 121 from left to right and from right to left.
</pre>
<p><strong class="example">Example 2:</strong></p>
<pre>
<strong>Input:</strong> x = -121
<strong>Output:</strong> false
<strong>Explanation:</strong> From left to right, it reads -121. From right to left, it becomes 121-. Therefore it is not a palindrome.
</pre>
<p><strong class="example">Example 3:</strong></p>
<pre>
<strong>Input:</strong> x = 10
<strong>Output:</strong> false
<strong>Explanation:</strong> Reads 01 from right to left. Therefore it is not a palindrome.
</pre>
<p> </p>
<p><strong>Constraints:</strong></p>
<ul>
<li><code>-2<sup>31</sup> <= x <= 2<sup>31</sup> - 1</code></li>
</ul>
<p> </p>
<strong>Follow up:</strong> Could you solve it without converting the integer to a string? | Easy | 6.2M | 10.5M | 6,159,089 | 10,462,661 | 58.9% | ['palindrome-linked-list', 'find-palindrome-with-fixed-length', 'strictly-palindromic-number', 'count-symmetric-integers', 'find-the-count-of-good-integers', 'find-the-largest-palindrome-divisible-by-k'] | [] | Algorithms | [{"value": "cpp", "text": "C++", "defaultCode": "class Solution {\npublic:\n bool isPalindrome(int x) {\n \n }\n};"}, {"value": "java", "text": "Java", "defaultCode": "class Solution {\n public boolean isPalindrome(int x) {\n \n }\n}"}, {"value": "python", "text": "Python", "defaultCode": "class Solution(object):\n def isPalindrome(self, x):\n \"\"\"\n :type x: int\n :rtype: bool\n \"\"\"\n "}, {"value": "python3", "text": "Python3", "defaultCode": "class Solution:\n def isPalindrome(self, x: int) -> bool:\n "}, {"value": "c", "text": "C", "defaultCode": "bool isPalindrome(int x) {\n \n}"}, {"value": "csharp", "text": "C#", "defaultCode": "public class Solution {\n public bool IsPalindrome(int x) {\n \n }\n}"}, {"value": "javascript", "text": "JavaScript", "defaultCode": "/**\n * @param {number} x\n * @return {boolean}\n */\nvar isPalindrome = function(x) {\n \n};"}, {"value": "typescript", "text": "TypeScript", "defaultCode": "function isPalindrome(x: number): boolean {\n \n};"}, {"value": "php", "text": "PHP", "defaultCode": "class Solution {\n\n /**\n * @param Integer $x\n * @return Boolean\n */\n function isPalindrome($x) {\n \n }\n}"}, {"value": "swift", "text": "Swift", "defaultCode": "class Solution {\n func isPalindrome(_ x: Int) -> Bool {\n \n }\n}"}, {"value": "kotlin", "text": "Kotlin", "defaultCode": "class Solution {\n fun isPalindrome(x: Int): Boolean {\n \n }\n}"}, {"value": "dart", "text": "Dart", "defaultCode": "class Solution {\n bool isPalindrome(int x) {\n \n }\n}"}, {"value": "golang", "text": "Go", "defaultCode": "func isPalindrome(x int) bool {\n \n}"}, {"value": "ruby", "text": "Ruby", "defaultCode": "# @param {Integer} x\n# @return {Boolean}\ndef is_palindrome(x)\n \nend"}, {"value": "scala", "text": "Scala", "defaultCode": "object Solution {\n def isPalindrome(x: Int): Boolean = {\n \n }\n}"}, {"value": "rust", "text": "Rust", "defaultCode": "impl Solution {\n pub fn is_palindrome(x: i32) -> bool {\n \n }\n}"}, {"value": "racket", "text": "Racket", "defaultCode": "(define/contract (is-palindrome x)\n (-> exact-integer? boolean?)\n )"}, {"value": "erlang", "text": "Erlang", "defaultCode": "-spec is_palindrome(X :: integer()) -> boolean().\nis_palindrome(X) ->\n ."}, {"value": "elixir", "text": "Elixir", "defaultCode": "defmodule Solution do\n @spec is_palindrome(x :: integer) :: boolean\n def is_palindrome(x) do\n \n end\nend"}] | 121 | {
"name": "isPalindrome",
"params": [
{
"name": "x",
"type": "integer"
}
],
"return": {
"type": "boolean"
}
} | {"cpp": ["C++", "<p>Compiled with <code> clang 19 </code> using the latest C++ 23 standard, and <code>libstdc++</code> provided by GCC 14.</p>\r\n\r\n<p>Your code is compiled with level two optimization (<code>-O2</code>). <a href=\"https://github.com/google/sanitizers/wiki/AddressSanitizer\" target=\"_blank\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>"], "java": ["Java", "<p><code>OpenJDK 21</code>. Using compile arguments: <code>--enable-preview --release 21</code></p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>\r\n<p>Includes <code>Pair</code> class from https://docs.oracle.com/javase/8/javafx/api/javafx/util/Pair.html.</p>"], "python": ["Python", "<p><code>Python 2.7.18</code>.</p>\r\n\r\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\"https://docs.python.org/2/library/array.html\" target=\"_blank\">array</a>, <a href=\"https://docs.python.org/2/library/bisect.html\" target=\"_blank\">bisect</a>, <a href=\"https://docs.python.org/2/library/collections.html\" target=\"_blank\">collections</a>. If you need more libraries, you can import it yourself.</p>\r\n\r\n<p>For Map/TreeMap data structure, you may use <a href=\"http://www.grantjenks.com/docs/sortedcontainers/\" target=\"_blank\">sortedcontainers</a> library.</p>\r\n\r\n<p>Note that Python 2.7 <a href=\"https://www.python.org/dev/peps/pep-0373/\" target=\"_blank\">is not maintained anymore</a>. For the latest Python, please choose Python3 instead.</p>"], "c": ["C", "<p>Compiled with <code>gcc 14</code> using the gnu11 standard.</p>\r\n\r\n<p>Your code is compiled with level one optimization (<code>-O2</code>). <a href=\"https://github.com/google/sanitizers/wiki/AddressSanitizer\" target=\"_blank\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>\r\n\r\n<p>For hash table operations, you may use <a href=\"https://troydhanson.github.io/uthash/\" target=\"_blank\">uthash</a>. \"uthash.h\" is included by default. Below are some examples:</p>\r\n\r\n<p><b>1. Adding an item to a hash.</b>\r\n<pre>\r\nstruct hash_entry {\r\n int id; /* we'll use this field as the key */\r\n char name[10];\r\n UT_hash_handle hh; /* makes this structure hashable */\r\n};\r\n\r\nstruct hash_entry *users = NULL;\r\n\r\nvoid add_user(struct hash_entry *s) {\r\n HASH_ADD_INT(users, id, s);\r\n}\r\n</pre>\r\n</p>\r\n\r\n<p><b>2. Looking up an item in a hash:</b>\r\n<pre>\r\nstruct hash_entry *find_user(int user_id) {\r\n struct hash_entry *s;\r\n HASH_FIND_INT(users, &user_id, s);\r\n return s;\r\n}\r\n</pre>\r\n</p>\r\n\r\n<p><b>3. Deleting an item in a hash:</b>\r\n<pre>\r\nvoid delete_user(struct hash_entry *user) {\r\n HASH_DEL(users, user); \r\n}\r\n</pre>\r\n</p>"], "csharp": ["C#", "<p><a href=\"https://learn.microsoft.com/en-us/dotnet/csharp/whats-new/csharp-13\" target=\"_blank\">C# 13</a> with .NET 9 runtime</p>"], "javascript": ["JavaScript", "<p><code>Node.js 22.14.0</code>.</p>\r\n\r\n<p>Your code is run with <code>--harmony</code> flag, enabling <a href=\"http://node.green/\" target=\"_blank\">new ES6 features</a>.</p>\r\n\r\n<p><a href=\"https://lodash.com\" target=\"_blank\">lodash.js</a> library is included by default.</p>\r\n\r\n<p>For Priority Queue / Queue data structures, you may use 6.3.2 version of <a href=\"https://github.com/datastructures-js/priority-queue/tree/v6.3.2\" target=\"_blank\">datastructures-js/priority-queue</a> and 4.2.3 version of <a href=\"https://github.com/datastructures-js/queue/tree/v4.2.3\" target=\"_blank\">datastructures-js/queue</a> and 1.0.4 version of <a href=\"https://github.com/datastructures-js/deque/tree/v1.0.4\" target=\"_blank\">datastructures-js/deque</a>.</p>"], "ruby": ["Ruby", "<p><code>Ruby 3.2</code></p>\r\n\r\n<p>Some common data structure implementations are provided in the Algorithms module: https://www.rubydoc.info/github/kanwei/algorithms/Algorithms</p>"], "swift": ["Swift", "<p><code>Swift 6.0</code>.</p>\r\n\r\n<p>You may use the following packages:<br/>\r\n<a href=\"https://github.com/apple/swift-algorithms/tree/1.2.0\" target=\"_blank\">swift-algorithms 1.2.0</a><br/>\r\n<a href=\"https://github.com/apple/swift-collections/tree/1.1.4\" target=\"_blank\">swift-collections 1.1.4</a><br/>\r\n<a href=\"https://github.com/apple/swift-numerics/tree/1.0.2\" target=\"_blank\">swift-numerics 1.0.2</a></p>"], "golang": ["Go", "<p><code>Go 1.23</code></p>\r\n<p>Support <a href=\"https://pkg.go.dev/github.com/emirpasic/[email protected]\" target=\"_blank\">https://pkg.go.dev/github.com/emirpasic/[email protected]</a> and <a href=\"https://pkg.go.dev/github.com/emirpasic/gods/[email protected]\" target=\"_blank\">https://pkg.go.dev/github.com/emirpasic/gods/[email protected]</a> library.</p>"], "python3": ["Python3", "<p><code>Python 3.11</code>.</p>\r\n\r\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\"https://docs.python.org/3/library/array.html\" target=\"_blank\">array</a>, <a href=\"https://docs.python.org/3/library/bisect.html\" target=\"_blank\">bisect</a>, <a href=\"https://docs.python.org/3/library/collections.html\" target=\"_blank\">collections</a>. If you need more libraries, you can import it yourself.</p>\r\n\r\n<p>For Map/TreeMap data structure, you may use <a href=\"http://www.grantjenks.com/docs/sortedcontainers/\" target=\"_blank\">sortedcontainers</a> library.</p>"], "scala": ["Scala", "<p><code>Scala 3.3.1</code>.</p>"], "kotlin": ["Kotlin", "<p><code>Kotlin 2.1.10</code>.</p>"], "rust": ["Rust", "<p><code>Rust 1.85.0</code>. Your code will be compiled with <code>opt-level</code> 2.</p>\r\n\r\n<p>Supports <a href=\"https://crates.io/crates/rand\" target=\"_blank\">rand v0.8</a> and <a href=\"https://crates.io/crates/regex\" target=\"_blank\">regex\u00a0v1</a> and <a href=\"https://crates.io/crates/itertools\" target=\"_blank\">itertools\u00a0v0.14</a> from crates.io</p>"], "php": ["PHP", "<p><code>PHP 8.2</code>.</p>\r\n<p>With bcmath module</p>"], "typescript": ["Typescript", "<p><code>TypeScript 5.7.3, Node.js 22.14.0</code>.</p>\r\n\r\n<p>Compile Options: <code>--alwaysStrict --strictBindCallApply --strictFunctionTypes --target ES2024</code></p>\r\n\r\n<p><a href=\"https://lodash.com\" target=\"_blank\">lodash.js</a> library is included by default.</p>\r\n\r\n<p>For Priority Queue / Queue data structures, you may use 6.3.2 version of <a href=\"https://github.com/datastructures-js/priority-queue/tree/v6.3.2\" target=\"_blank\">datastructures-js/priority-queue</a> and 4.2.3 version of <a href=\"https://github.com/datastructures-js/queue/tree/v4.2.3\" target=\"_blank\">datastructures-js/queue</a> and 1.0.4 version of <a href=\"https://github.com/datastructures-js/deque/tree/v1.0.4\" target=\"_blank\">datastructures-js/deque</a>.</p>"], "racket": ["Racket", "<p><a href=\"https://docs.racket-lang.org/guide/performance.html#%28tech._c%29\" target=\"_blank\">Racket CS</a> v8.15</p>\r\n\r\n<p>Using <code>#lang racket</code></p>\r\n\r\n<p>Required <code>data/gvector data/queue data/order data/heap</code> automatically for your convenience</p>"], "erlang": ["Erlang", "Erlang/OTP 26"], "elixir": ["Elixir", "Elixir 1.17 with Erlang/OTP 26"], "dart": ["Dart", "<p>Dart 3.2. You may use package <a href=\"https://pub.dev/packages/collection/versions/1.18.0\" target=\"_blank\">collection</a></p>\r\n\r\n<p>Your code will be run directly without compiling</p>"]} | ['Math'] |
10 | Regular Expression Matching | regular-expression-matching | <p>Given an input string <code>s</code> and a pattern <code>p</code>, implement regular expression matching with support for <code>'.'</code> and <code>'*'</code> where:</p>
<ul>
<li><code>'.'</code> Matches any single character.</li>
<li><code>'*'</code> Matches zero or more of the preceding element.</li>
</ul>
<p>The matching should cover the <strong>entire</strong> input string (not partial).</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<strong>Input:</strong> s = "aa", p = "a"
<strong>Output:</strong> false
<strong>Explanation:</strong> "a" does not match the entire string "aa".
</pre>
<p><strong class="example">Example 2:</strong></p>
<pre>
<strong>Input:</strong> s = "aa", p = "a*"
<strong>Output:</strong> true
<strong>Explanation:</strong> '*' means zero or more of the preceding element, 'a'. Therefore, by repeating 'a' once, it becomes "aa".
</pre>
<p><strong class="example">Example 3:</strong></p>
<pre>
<strong>Input:</strong> s = "ab", p = ".*"
<strong>Output:</strong> true
<strong>Explanation:</strong> ".*" means "zero or more (*) of any character (.)".
</pre>
<p> </p>
<p><strong>Constraints:</strong></p>
<ul>
<li><code>1 <= s.length <= 20</code></li>
<li><code>1 <= p.length <= 20</code></li>
<li><code>s</code> contains only lowercase English letters.</li>
<li><code>p</code> contains only lowercase English letters, <code>'.'</code>, and <code>'*'</code>.</li>
<li>It is guaranteed for each appearance of the character <code>'*'</code>, there will be a previous valid character to match.</li>
</ul>
| Hard | 1.1M | 3.9M | 1,131,845 | 3,893,591 | 29.1% | ['wildcard-matching'] | [] | Algorithms | [{"value": "cpp", "text": "C++", "defaultCode": "class Solution {\npublic:\n bool isMatch(string s, string p) {\n \n }\n};"}, {"value": "java", "text": "Java", "defaultCode": "class Solution {\n public boolean isMatch(String s, String p) {\n \n }\n}"}, {"value": "python", "text": "Python", "defaultCode": "class Solution(object):\n def isMatch(self, s, p):\n \"\"\"\n :type s: str\n :type p: str\n :rtype: bool\n \"\"\"\n "}, {"value": "python3", "text": "Python3", "defaultCode": "class Solution:\n def isMatch(self, s: str, p: str) -> bool:\n "}, {"value": "c", "text": "C", "defaultCode": "bool isMatch(char* s, char* p) {\n \n}"}, {"value": "csharp", "text": "C#", "defaultCode": "public class Solution {\n public bool IsMatch(string s, string p) {\n \n }\n}"}, {"value": "javascript", "text": "JavaScript", "defaultCode": "/**\n * @param {string} s\n * @param {string} p\n * @return {boolean}\n */\nvar isMatch = function(s, p) {\n \n};"}, {"value": "typescript", "text": "TypeScript", "defaultCode": "function isMatch(s: string, p: string): boolean {\n \n};"}, {"value": "php", "text": "PHP", "defaultCode": "class Solution {\n\n /**\n * @param String $s\n * @param String $p\n * @return Boolean\n */\n function isMatch($s, $p) {\n \n }\n}"}, {"value": "swift", "text": "Swift", "defaultCode": "class Solution {\n func isMatch(_ s: String, _ p: String) -> Bool {\n \n }\n}"}, {"value": "kotlin", "text": "Kotlin", "defaultCode": "class Solution {\n fun isMatch(s: String, p: String): Boolean {\n \n }\n}"}, {"value": "dart", "text": "Dart", "defaultCode": "class Solution {\n bool isMatch(String s, String p) {\n \n }\n}"}, {"value": "golang", "text": "Go", "defaultCode": "func isMatch(s string, p string) bool {\n \n}"}, {"value": "ruby", "text": "Ruby", "defaultCode": "# @param {String} s\n# @param {String} p\n# @return {Boolean}\ndef is_match(s, p)\n \nend"}, {"value": "scala", "text": "Scala", "defaultCode": "object Solution {\n def isMatch(s: String, p: String): Boolean = {\n \n }\n}"}, {"value": "rust", "text": "Rust", "defaultCode": "impl Solution {\n pub fn is_match(s: String, p: String) -> bool {\n \n }\n}"}, {"value": "racket", "text": "Racket", "defaultCode": "(define/contract (is-match s p)\n (-> string? string? boolean?)\n )"}, {"value": "erlang", "text": "Erlang", "defaultCode": "-spec is_match(S :: unicode:unicode_binary(), P :: unicode:unicode_binary()) -> boolean().\nis_match(S, P) ->\n ."}, {"value": "elixir", "text": "Elixir", "defaultCode": "defmodule Solution do\n @spec is_match(s :: String.t, p :: String.t) :: boolean\n def is_match(s, p) do\n \n end\nend"}] | "aa"
"a" | {
"name": "isMatch",
"params": [
{
"name": "s",
"type": "string"
},
{
"name": "p",
"type": "string"
}
],
"return": {
"type": "boolean"
}
} | {"cpp": ["C++", "<p>Compiled with <code> clang 19 </code> using the latest C++ 23 standard, and <code>libstdc++</code> provided by GCC 14.</p>\r\n\r\n<p>Your code is compiled with level two optimization (<code>-O2</code>). <a href=\"https://github.com/google/sanitizers/wiki/AddressSanitizer\" target=\"_blank\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>"], "java": ["Java", "<p><code>OpenJDK 21</code>. Using compile arguments: <code>--enable-preview --release 21</code></p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>\r\n<p>Includes <code>Pair</code> class from https://docs.oracle.com/javase/8/javafx/api/javafx/util/Pair.html.</p>"], "python": ["Python", "<p><code>Python 2.7.18</code>.</p>\r\n\r\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\"https://docs.python.org/2/library/array.html\" target=\"_blank\">array</a>, <a href=\"https://docs.python.org/2/library/bisect.html\" target=\"_blank\">bisect</a>, <a href=\"https://docs.python.org/2/library/collections.html\" target=\"_blank\">collections</a>. If you need more libraries, you can import it yourself.</p>\r\n\r\n<p>For Map/TreeMap data structure, you may use <a href=\"http://www.grantjenks.com/docs/sortedcontainers/\" target=\"_blank\">sortedcontainers</a> library.</p>\r\n\r\n<p>Note that Python 2.7 <a href=\"https://www.python.org/dev/peps/pep-0373/\" target=\"_blank\">is not maintained anymore</a>. For the latest Python, please choose Python3 instead.</p>"], "c": ["C", "<p>Compiled with <code>gcc 14</code> using the gnu11 standard.</p>\r\n\r\n<p>Your code is compiled with level one optimization (<code>-O2</code>). <a href=\"https://github.com/google/sanitizers/wiki/AddressSanitizer\" target=\"_blank\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>\r\n\r\n<p>For hash table operations, you may use <a href=\"https://troydhanson.github.io/uthash/\" target=\"_blank\">uthash</a>. \"uthash.h\" is included by default. Below are some examples:</p>\r\n\r\n<p><b>1. Adding an item to a hash.</b>\r\n<pre>\r\nstruct hash_entry {\r\n int id; /* we'll use this field as the key */\r\n char name[10];\r\n UT_hash_handle hh; /* makes this structure hashable */\r\n};\r\n\r\nstruct hash_entry *users = NULL;\r\n\r\nvoid add_user(struct hash_entry *s) {\r\n HASH_ADD_INT(users, id, s);\r\n}\r\n</pre>\r\n</p>\r\n\r\n<p><b>2. Looking up an item in a hash:</b>\r\n<pre>\r\nstruct hash_entry *find_user(int user_id) {\r\n struct hash_entry *s;\r\n HASH_FIND_INT(users, &user_id, s);\r\n return s;\r\n}\r\n</pre>\r\n</p>\r\n\r\n<p><b>3. Deleting an item in a hash:</b>\r\n<pre>\r\nvoid delete_user(struct hash_entry *user) {\r\n HASH_DEL(users, user); \r\n}\r\n</pre>\r\n</p>"], "csharp": ["C#", "<p><a href=\"https://learn.microsoft.com/en-us/dotnet/csharp/whats-new/csharp-13\" target=\"_blank\">C# 13</a> with .NET 9 runtime</p>"], "javascript": ["JavaScript", "<p><code>Node.js 22.14.0</code>.</p>\r\n\r\n<p>Your code is run with <code>--harmony</code> flag, enabling <a href=\"http://node.green/\" target=\"_blank\">new ES6 features</a>.</p>\r\n\r\n<p><a href=\"https://lodash.com\" target=\"_blank\">lodash.js</a> library is included by default.</p>\r\n\r\n<p>For Priority Queue / Queue data structures, you may use 6.3.2 version of <a href=\"https://github.com/datastructures-js/priority-queue/tree/v6.3.2\" target=\"_blank\">datastructures-js/priority-queue</a> and 4.2.3 version of <a href=\"https://github.com/datastructures-js/queue/tree/v4.2.3\" target=\"_blank\">datastructures-js/queue</a> and 1.0.4 version of <a href=\"https://github.com/datastructures-js/deque/tree/v1.0.4\" target=\"_blank\">datastructures-js/deque</a>.</p>"], "ruby": ["Ruby", "<p><code>Ruby 3.2</code></p>\r\n\r\n<p>Some common data structure implementations are provided in the Algorithms module: https://www.rubydoc.info/github/kanwei/algorithms/Algorithms</p>"], "swift": ["Swift", "<p><code>Swift 6.0</code>.</p>\r\n\r\n<p>You may use the following packages:<br/>\r\n<a href=\"https://github.com/apple/swift-algorithms/tree/1.2.0\" target=\"_blank\">swift-algorithms 1.2.0</a><br/>\r\n<a href=\"https://github.com/apple/swift-collections/tree/1.1.4\" target=\"_blank\">swift-collections 1.1.4</a><br/>\r\n<a href=\"https://github.com/apple/swift-numerics/tree/1.0.2\" target=\"_blank\">swift-numerics 1.0.2</a></p>"], "golang": ["Go", "<p><code>Go 1.23</code></p>\r\n<p>Support <a href=\"https://pkg.go.dev/github.com/emirpasic/[email protected]\" target=\"_blank\">https://pkg.go.dev/github.com/emirpasic/[email protected]</a> and <a href=\"https://pkg.go.dev/github.com/emirpasic/gods/[email protected]\" target=\"_blank\">https://pkg.go.dev/github.com/emirpasic/gods/[email protected]</a> library.</p>"], "python3": ["Python3", "<p><code>Python 3.11</code>.</p>\r\n\r\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\"https://docs.python.org/3/library/array.html\" target=\"_blank\">array</a>, <a href=\"https://docs.python.org/3/library/bisect.html\" target=\"_blank\">bisect</a>, <a href=\"https://docs.python.org/3/library/collections.html\" target=\"_blank\">collections</a>. If you need more libraries, you can import it yourself.</p>\r\n\r\n<p>For Map/TreeMap data structure, you may use <a href=\"http://www.grantjenks.com/docs/sortedcontainers/\" target=\"_blank\">sortedcontainers</a> library.</p>"], "scala": ["Scala", "<p><code>Scala 3.3.1</code>.</p>"], "kotlin": ["Kotlin", "<p><code>Kotlin 2.1.10</code>.</p>"], "rust": ["Rust", "<p><code>Rust 1.85.0</code>. Your code will be compiled with <code>opt-level</code> 2.</p>\r\n\r\n<p>Supports <a href=\"https://crates.io/crates/rand\" target=\"_blank\">rand v0.8</a> and <a href=\"https://crates.io/crates/regex\" target=\"_blank\">regex\u00a0v1</a> and <a href=\"https://crates.io/crates/itertools\" target=\"_blank\">itertools\u00a0v0.14</a> from crates.io</p>"], "php": ["PHP", "<p><code>PHP 8.2</code>.</p>\r\n<p>With bcmath module</p>"], "typescript": ["Typescript", "<p><code>TypeScript 5.7.3, Node.js 22.14.0</code>.</p>\r\n\r\n<p>Compile Options: <code>--alwaysStrict --strictBindCallApply --strictFunctionTypes --target ES2024</code></p>\r\n\r\n<p><a href=\"https://lodash.com\" target=\"_blank\">lodash.js</a> library is included by default.</p>\r\n\r\n<p>For Priority Queue / Queue data structures, you may use 6.3.2 version of <a href=\"https://github.com/datastructures-js/priority-queue/tree/v6.3.2\" target=\"_blank\">datastructures-js/priority-queue</a> and 4.2.3 version of <a href=\"https://github.com/datastructures-js/queue/tree/v4.2.3\" target=\"_blank\">datastructures-js/queue</a> and 1.0.4 version of <a href=\"https://github.com/datastructures-js/deque/tree/v1.0.4\" target=\"_blank\">datastructures-js/deque</a>.</p>"], "racket": ["Racket", "<p><a href=\"https://docs.racket-lang.org/guide/performance.html#%28tech._c%29\" target=\"_blank\">Racket CS</a> v8.15</p>\r\n\r\n<p>Using <code>#lang racket</code></p>\r\n\r\n<p>Required <code>data/gvector data/queue data/order data/heap</code> automatically for your convenience</p>"], "erlang": ["Erlang", "Erlang/OTP 26"], "elixir": ["Elixir", "Elixir 1.17 with Erlang/OTP 26"], "dart": ["Dart", "<p>Dart 3.2. You may use package <a href=\"https://pub.dev/packages/collection/versions/1.18.0\" target=\"_blank\">collection</a></p>\r\n\r\n<p>Your code will be run directly without compiling</p>"]} | ['String', 'Dynamic Programming', 'Recursion'] |
11 | Container With Most Water | container-with-most-water | <p>You are given an integer array <code>height</code> of length <code>n</code>. There are <code>n</code> vertical lines drawn such that the two endpoints of the <code>i<sup>th</sup></code> line are <code>(i, 0)</code> and <code>(i, height[i])</code>.</p>
<p>Find two lines that together with the x-axis form a container, such that the container contains the most water.</p>
<p>Return <em>the maximum amount of water a container can store</em>.</p>
<p><strong>Notice</strong> that you may not slant the container.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<img alt="" src="https://s3-lc-upload.s3.amazonaws.com/uploads/2018/07/17/question_11.jpg" style="width: 600px; height: 287px;" />
<pre>
<strong>Input:</strong> height = [1,8,6,2,5,4,8,3,7]
<strong>Output:</strong> 49
<strong>Explanation:</strong> The above vertical lines are represented by array [1,8,6,2,5,4,8,3,7]. In this case, the max area of water (blue section) the container can contain is 49.
</pre>
<p><strong class="example">Example 2:</strong></p>
<pre>
<strong>Input:</strong> height = [1,1]
<strong>Output:</strong> 1
</pre>
<p> </p>
<p><strong>Constraints:</strong></p>
<ul>
<li><code>n == height.length</code></li>
<li><code>2 <= n <= 10<sup>5</sup></code></li>
<li><code>0 <= height[i] <= 10<sup>4</sup></code></li>
</ul>
| Medium | 3.9M | 6.8M | 3,927,910 | 6,842,402 | 57.4% | ['trapping-rain-water', 'maximum-tastiness-of-candy-basket', 'house-robber-iv'] | [] | Algorithms | [{"value": "cpp", "text": "C++", "defaultCode": "class Solution {\npublic:\n int maxArea(vector<int>& height) {\n \n }\n};"}, {"value": "java", "text": "Java", "defaultCode": "class Solution {\n public int maxArea(int[] height) {\n \n }\n}"}, {"value": "python", "text": "Python", "defaultCode": "class Solution(object):\n def maxArea(self, height):\n \"\"\"\n :type height: List[int]\n :rtype: int\n \"\"\"\n "}, {"value": "python3", "text": "Python3", "defaultCode": "class Solution:\n def maxArea(self, height: List[int]) -> int:\n "}, {"value": "c", "text": "C", "defaultCode": "int maxArea(int* height, int heightSize) {\n \n}"}, {"value": "csharp", "text": "C#", "defaultCode": "public class Solution {\n public int MaxArea(int[] height) {\n \n }\n}"}, {"value": "javascript", "text": "JavaScript", "defaultCode": "/**\n * @param {number[]} height\n * @return {number}\n */\nvar maxArea = function(height) {\n \n};"}, {"value": "typescript", "text": "TypeScript", "defaultCode": "function maxArea(height: number[]): number {\n \n};"}, {"value": "php", "text": "PHP", "defaultCode": "class Solution {\n\n /**\n * @param Integer[] $height\n * @return Integer\n */\n function maxArea($height) {\n \n }\n}"}, {"value": "swift", "text": "Swift", "defaultCode": "class Solution {\n func maxArea(_ height: [Int]) -> Int {\n \n }\n}"}, {"value": "kotlin", "text": "Kotlin", "defaultCode": "class Solution {\n fun maxArea(height: IntArray): Int {\n \n }\n}"}, {"value": "dart", "text": "Dart", "defaultCode": "class Solution {\n int maxArea(List<int> height) {\n \n }\n}"}, {"value": "golang", "text": "Go", "defaultCode": "func maxArea(height []int) int {\n \n}"}, {"value": "ruby", "text": "Ruby", "defaultCode": "# @param {Integer[]} height\n# @return {Integer}\ndef max_area(height)\n \nend"}, {"value": "scala", "text": "Scala", "defaultCode": "object Solution {\n def maxArea(height: Array[Int]): Int = {\n \n }\n}"}, {"value": "rust", "text": "Rust", "defaultCode": "impl Solution {\n pub fn max_area(height: Vec<i32>) -> i32 {\n \n }\n}"}, {"value": "racket", "text": "Racket", "defaultCode": "(define/contract (max-area height)\n (-> (listof exact-integer?) exact-integer?)\n )"}, {"value": "erlang", "text": "Erlang", "defaultCode": "-spec max_area(Height :: [integer()]) -> integer().\nmax_area(Height) ->\n ."}, {"value": "elixir", "text": "Elixir", "defaultCode": "defmodule Solution do\n @spec max_area(height :: [integer]) :: integer\n def max_area(height) do\n \n end\nend"}] | [1,8,6,2,5,4,8,3,7] | {
"name": "maxArea",
"params": [
{
"name": "height",
"type": "integer[]"
}
],
"return": {
"type": "integer"
}
} | {"cpp": ["C++", "<p>Compiled with <code> clang 19 </code> using the latest C++ 23 standard, and <code>libstdc++</code> provided by GCC 14.</p>\r\n\r\n<p>Your code is compiled with level two optimization (<code>-O2</code>). <a href=\"https://github.com/google/sanitizers/wiki/AddressSanitizer\" target=\"_blank\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>"], "java": ["Java", "<p><code>OpenJDK 21</code>. Using compile arguments: <code>--enable-preview --release 21</code></p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>\r\n<p>Includes <code>Pair</code> class from https://docs.oracle.com/javase/8/javafx/api/javafx/util/Pair.html.</p>"], "python": ["Python", "<p><code>Python 2.7.18</code>.</p>\r\n\r\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\"https://docs.python.org/2/library/array.html\" target=\"_blank\">array</a>, <a href=\"https://docs.python.org/2/library/bisect.html\" target=\"_blank\">bisect</a>, <a href=\"https://docs.python.org/2/library/collections.html\" target=\"_blank\">collections</a>. If you need more libraries, you can import it yourself.</p>\r\n\r\n<p>For Map/TreeMap data structure, you may use <a href=\"http://www.grantjenks.com/docs/sortedcontainers/\" target=\"_blank\">sortedcontainers</a> library.</p>\r\n\r\n<p>Note that Python 2.7 <a href=\"https://www.python.org/dev/peps/pep-0373/\" target=\"_blank\">is not maintained anymore</a>. For the latest Python, please choose Python3 instead.</p>"], "c": ["C", "<p>Compiled with <code>gcc 14</code> using the gnu11 standard.</p>\r\n\r\n<p>Your code is compiled with level one optimization (<code>-O2</code>). <a href=\"https://github.com/google/sanitizers/wiki/AddressSanitizer\" target=\"_blank\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>\r\n\r\n<p>For hash table operations, you may use <a href=\"https://troydhanson.github.io/uthash/\" target=\"_blank\">uthash</a>. \"uthash.h\" is included by default. Below are some examples:</p>\r\n\r\n<p><b>1. Adding an item to a hash.</b>\r\n<pre>\r\nstruct hash_entry {\r\n int id; /* we'll use this field as the key */\r\n char name[10];\r\n UT_hash_handle hh; /* makes this structure hashable */\r\n};\r\n\r\nstruct hash_entry *users = NULL;\r\n\r\nvoid add_user(struct hash_entry *s) {\r\n HASH_ADD_INT(users, id, s);\r\n}\r\n</pre>\r\n</p>\r\n\r\n<p><b>2. Looking up an item in a hash:</b>\r\n<pre>\r\nstruct hash_entry *find_user(int user_id) {\r\n struct hash_entry *s;\r\n HASH_FIND_INT(users, &user_id, s);\r\n return s;\r\n}\r\n</pre>\r\n</p>\r\n\r\n<p><b>3. Deleting an item in a hash:</b>\r\n<pre>\r\nvoid delete_user(struct hash_entry *user) {\r\n HASH_DEL(users, user); \r\n}\r\n</pre>\r\n</p>"], "csharp": ["C#", "<p><a href=\"https://learn.microsoft.com/en-us/dotnet/csharp/whats-new/csharp-13\" target=\"_blank\">C# 13</a> with .NET 9 runtime</p>"], "javascript": ["JavaScript", "<p><code>Node.js 22.14.0</code>.</p>\r\n\r\n<p>Your code is run with <code>--harmony</code> flag, enabling <a href=\"http://node.green/\" target=\"_blank\">new ES6 features</a>.</p>\r\n\r\n<p><a href=\"https://lodash.com\" target=\"_blank\">lodash.js</a> library is included by default.</p>\r\n\r\n<p>For Priority Queue / Queue data structures, you may use 6.3.2 version of <a href=\"https://github.com/datastructures-js/priority-queue/tree/v6.3.2\" target=\"_blank\">datastructures-js/priority-queue</a> and 4.2.3 version of <a href=\"https://github.com/datastructures-js/queue/tree/v4.2.3\" target=\"_blank\">datastructures-js/queue</a> and 1.0.4 version of <a href=\"https://github.com/datastructures-js/deque/tree/v1.0.4\" target=\"_blank\">datastructures-js/deque</a>.</p>"], "ruby": ["Ruby", "<p><code>Ruby 3.2</code></p>\r\n\r\n<p>Some common data structure implementations are provided in the Algorithms module: https://www.rubydoc.info/github/kanwei/algorithms/Algorithms</p>"], "swift": ["Swift", "<p><code>Swift 6.0</code>.</p>\r\n\r\n<p>You may use the following packages:<br/>\r\n<a href=\"https://github.com/apple/swift-algorithms/tree/1.2.0\" target=\"_blank\">swift-algorithms 1.2.0</a><br/>\r\n<a href=\"https://github.com/apple/swift-collections/tree/1.1.4\" target=\"_blank\">swift-collections 1.1.4</a><br/>\r\n<a href=\"https://github.com/apple/swift-numerics/tree/1.0.2\" target=\"_blank\">swift-numerics 1.0.2</a></p>"], "golang": ["Go", "<p><code>Go 1.23</code></p>\r\n<p>Support <a href=\"https://pkg.go.dev/github.com/emirpasic/[email protected]\" target=\"_blank\">https://pkg.go.dev/github.com/emirpasic/[email protected]</a> and <a href=\"https://pkg.go.dev/github.com/emirpasic/gods/[email protected]\" target=\"_blank\">https://pkg.go.dev/github.com/emirpasic/gods/[email protected]</a> library.</p>"], "python3": ["Python3", "<p><code>Python 3.11</code>.</p>\r\n\r\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\"https://docs.python.org/3/library/array.html\" target=\"_blank\">array</a>, <a href=\"https://docs.python.org/3/library/bisect.html\" target=\"_blank\">bisect</a>, <a href=\"https://docs.python.org/3/library/collections.html\" target=\"_blank\">collections</a>. If you need more libraries, you can import it yourself.</p>\r\n\r\n<p>For Map/TreeMap data structure, you may use <a href=\"http://www.grantjenks.com/docs/sortedcontainers/\" target=\"_blank\">sortedcontainers</a> library.</p>"], "scala": ["Scala", "<p><code>Scala 3.3.1</code>.</p>"], "kotlin": ["Kotlin", "<p><code>Kotlin 2.1.10</code>.</p>"], "rust": ["Rust", "<p><code>Rust 1.85.0</code>. Your code will be compiled with <code>opt-level</code> 2.</p>\r\n\r\n<p>Supports <a href=\"https://crates.io/crates/rand\" target=\"_blank\">rand v0.8</a> and <a href=\"https://crates.io/crates/regex\" target=\"_blank\">regex\u00a0v1</a> and <a href=\"https://crates.io/crates/itertools\" target=\"_blank\">itertools\u00a0v0.14</a> from crates.io</p>"], "php": ["PHP", "<p><code>PHP 8.2</code>.</p>\r\n<p>With bcmath module</p>"], "typescript": ["Typescript", "<p><code>TypeScript 5.7.3, Node.js 22.14.0</code>.</p>\r\n\r\n<p>Compile Options: <code>--alwaysStrict --strictBindCallApply --strictFunctionTypes --target ES2024</code></p>\r\n\r\n<p><a href=\"https://lodash.com\" target=\"_blank\">lodash.js</a> library is included by default.</p>\r\n\r\n<p>For Priority Queue / Queue data structures, you may use 6.3.2 version of <a href=\"https://github.com/datastructures-js/priority-queue/tree/v6.3.2\" target=\"_blank\">datastructures-js/priority-queue</a> and 4.2.3 version of <a href=\"https://github.com/datastructures-js/queue/tree/v4.2.3\" target=\"_blank\">datastructures-js/queue</a> and 1.0.4 version of <a href=\"https://github.com/datastructures-js/deque/tree/v1.0.4\" target=\"_blank\">datastructures-js/deque</a>.</p>"], "racket": ["Racket", "<p><a href=\"https://docs.racket-lang.org/guide/performance.html#%28tech._c%29\" target=\"_blank\">Racket CS</a> v8.15</p>\r\n\r\n<p>Using <code>#lang racket</code></p>\r\n\r\n<p>Required <code>data/gvector data/queue data/order data/heap</code> automatically for your convenience</p>"], "erlang": ["Erlang", "Erlang/OTP 26"], "elixir": ["Elixir", "Elixir 1.17 with Erlang/OTP 26"], "dart": ["Dart", "<p>Dart 3.2. You may use package <a href=\"https://pub.dev/packages/collection/versions/1.18.0\" target=\"_blank\">collection</a></p>\r\n\r\n<p>Your code will be run directly without compiling</p>"]} | ['Array', 'Two Pointers', 'Greedy'] |
12 | Integer to Roman | integer-to-roman | <p>Seven different symbols represent Roman numerals with the following values:</p>
<table>
<thead>
<tr>
<th>Symbol</th>
<th>Value</th>
</tr>
</thead>
<tbody>
<tr>
<td>I</td>
<td>1</td>
</tr>
<tr>
<td>V</td>
<td>5</td>
</tr>
<tr>
<td>X</td>
<td>10</td>
</tr>
<tr>
<td>L</td>
<td>50</td>
</tr>
<tr>
<td>C</td>
<td>100</td>
</tr>
<tr>
<td>D</td>
<td>500</td>
</tr>
<tr>
<td>M</td>
<td>1000</td>
</tr>
</tbody>
</table>
<p>Roman numerals are formed by appending the conversions of decimal place values from highest to lowest. Converting a decimal place value into a Roman numeral has the following rules:</p>
<ul>
<li>If the value does not start with 4 or 9, select the symbol of the maximal value that can be subtracted from the input, append that symbol to the result, subtract its value, and convert the remainder to a Roman numeral.</li>
<li>If the value starts with 4 or 9 use the <strong>subtractive form</strong> representing one symbol subtracted from the following symbol, for example, 4 is 1 (<code>I</code>) less than 5 (<code>V</code>): <code>IV</code> and 9 is 1 (<code>I</code>) less than 10 (<code>X</code>): <code>IX</code>. Only the following subtractive forms are used: 4 (<code>IV</code>), 9 (<code>IX</code>), 40 (<code>XL</code>), 90 (<code>XC</code>), 400 (<code>CD</code>) and 900 (<code>CM</code>).</li>
<li>Only powers of 10 (<code>I</code>, <code>X</code>, <code>C</code>, <code>M</code>) can be appended consecutively at most 3 times to represent multiples of 10. You cannot append 5 (<code>V</code>), 50 (<code>L</code>), or 500 (<code>D</code>) multiple times. If you need to append a symbol 4 times use the <strong>subtractive form</strong>.</li>
</ul>
<p>Given an integer, convert it to a Roman numeral.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<div class="example-block">
<p><strong>Input:</strong> <span class="example-io">num = 3749</span></p>
<p><strong>Output:</strong> <span class="example-io">"MMMDCCXLIX"</span></p>
<p><strong>Explanation:</strong></p>
<pre>
3000 = MMM as 1000 (M) + 1000 (M) + 1000 (M)
700 = DCC as 500 (D) + 100 (C) + 100 (C)
40 = XL as 10 (X) less of 50 (L)
9 = IX as 1 (I) less of 10 (X)
Note: 49 is not 1 (I) less of 50 (L) because the conversion is based on decimal places
</pre>
</div>
<p><strong class="example">Example 2:</strong></p>
<div class="example-block">
<p><strong>Input:</strong> <span class="example-io">num = 58</span></p>
<p><strong>Output:</strong> <span class="example-io">"LVIII"</span></p>
<p><strong>Explanation:</strong></p>
<pre>
50 = L
8 = VIII
</pre>
</div>
<p><strong class="example">Example 3:</strong></p>
<div class="example-block">
<p><strong>Input:</strong> <span class="example-io">num = 1994</span></p>
<p><strong>Output:</strong> <span class="example-io">"MCMXCIV"</span></p>
<p><strong>Explanation:</strong></p>
<pre>
1000 = M
900 = CM
90 = XC
4 = IV
</pre>
</div>
<p> </p>
<p><strong>Constraints:</strong></p>
<ul>
<li><code>1 <= num <= 3999</code></li>
</ul>
| Medium | 1.7M | 2.5M | 1,676,934 | 2,462,404 | 68.1% | ['roman-to-integer', 'integer-to-english-words'] | [] | Algorithms | [{"value": "cpp", "text": "C++", "defaultCode": "class Solution {\npublic:\n string intToRoman(int num) {\n \n }\n};"}, {"value": "java", "text": "Java", "defaultCode": "class Solution {\n public String intToRoman(int num) {\n \n }\n}"}, {"value": "python", "text": "Python", "defaultCode": "class Solution(object):\n def intToRoman(self, num):\n \"\"\"\n :type num: int\n :rtype: str\n \"\"\"\n "}, {"value": "python3", "text": "Python3", "defaultCode": "class Solution:\n def intToRoman(self, num: int) -> str:\n "}, {"value": "c", "text": "C", "defaultCode": "char* intToRoman(int num) {\n \n}"}, {"value": "csharp", "text": "C#", "defaultCode": "public class Solution {\n public string IntToRoman(int num) {\n \n }\n}"}, {"value": "javascript", "text": "JavaScript", "defaultCode": "/**\n * @param {number} num\n * @return {string}\n */\nvar intToRoman = function(num) {\n \n};"}, {"value": "typescript", "text": "TypeScript", "defaultCode": "function intToRoman(num: number): string {\n \n};"}, {"value": "php", "text": "PHP", "defaultCode": "class Solution {\n\n /**\n * @param Integer $num\n * @return String\n */\n function intToRoman($num) {\n \n }\n}"}, {"value": "swift", "text": "Swift", "defaultCode": "class Solution {\n func intToRoman(_ num: Int) -> String {\n \n }\n}"}, {"value": "kotlin", "text": "Kotlin", "defaultCode": "class Solution {\n fun intToRoman(num: Int): String {\n \n }\n}"}, {"value": "dart", "text": "Dart", "defaultCode": "class Solution {\n String intToRoman(int num) {\n \n }\n}"}, {"value": "golang", "text": "Go", "defaultCode": "func intToRoman(num int) string {\n \n}"}, {"value": "ruby", "text": "Ruby", "defaultCode": "# @param {Integer} num\n# @return {String}\ndef int_to_roman(num)\n \nend"}, {"value": "scala", "text": "Scala", "defaultCode": "object Solution {\n def intToRoman(num: Int): String = {\n \n }\n}"}, {"value": "rust", "text": "Rust", "defaultCode": "impl Solution {\n pub fn int_to_roman(num: i32) -> String {\n \n }\n}"}, {"value": "racket", "text": "Racket", "defaultCode": "(define/contract (int-to-roman num)\n (-> exact-integer? string?)\n )"}, {"value": "erlang", "text": "Erlang", "defaultCode": "-spec int_to_roman(Num :: integer()) -> unicode:unicode_binary().\nint_to_roman(Num) ->\n ."}, {"value": "elixir", "text": "Elixir", "defaultCode": "defmodule Solution do\n @spec int_to_roman(num :: integer) :: String.t\n def int_to_roman(num) do\n \n end\nend"}] | 3749 | {
"name": "intToRoman",
"params": [
{
"name": "num",
"type": "integer"
}
],
"return": {
"type": "string"
}
} | {"cpp": ["C++", "<p>Compiled with <code> clang 19 </code> using the latest C++ 23 standard, and <code>libstdc++</code> provided by GCC 14.</p>\r\n\r\n<p>Your code is compiled with level two optimization (<code>-O2</code>). <a href=\"https://github.com/google/sanitizers/wiki/AddressSanitizer\" target=\"_blank\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>"], "java": ["Java", "<p><code>OpenJDK 21</code>. Using compile arguments: <code>--enable-preview --release 21</code></p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>\r\n<p>Includes <code>Pair</code> class from https://docs.oracle.com/javase/8/javafx/api/javafx/util/Pair.html.</p>"], "python": ["Python", "<p><code>Python 2.7.18</code>.</p>\r\n\r\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\"https://docs.python.org/2/library/array.html\" target=\"_blank\">array</a>, <a href=\"https://docs.python.org/2/library/bisect.html\" target=\"_blank\">bisect</a>, <a href=\"https://docs.python.org/2/library/collections.html\" target=\"_blank\">collections</a>. If you need more libraries, you can import it yourself.</p>\r\n\r\n<p>For Map/TreeMap data structure, you may use <a href=\"http://www.grantjenks.com/docs/sortedcontainers/\" target=\"_blank\">sortedcontainers</a> library.</p>\r\n\r\n<p>Note that Python 2.7 <a href=\"https://www.python.org/dev/peps/pep-0373/\" target=\"_blank\">is not maintained anymore</a>. For the latest Python, please choose Python3 instead.</p>"], "c": ["C", "<p>Compiled with <code>gcc 14</code> using the gnu11 standard.</p>\r\n\r\n<p>Your code is compiled with level one optimization (<code>-O2</code>). <a href=\"https://github.com/google/sanitizers/wiki/AddressSanitizer\" target=\"_blank\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>\r\n\r\n<p>For hash table operations, you may use <a href=\"https://troydhanson.github.io/uthash/\" target=\"_blank\">uthash</a>. \"uthash.h\" is included by default. Below are some examples:</p>\r\n\r\n<p><b>1. Adding an item to a hash.</b>\r\n<pre>\r\nstruct hash_entry {\r\n int id; /* we'll use this field as the key */\r\n char name[10];\r\n UT_hash_handle hh; /* makes this structure hashable */\r\n};\r\n\r\nstruct hash_entry *users = NULL;\r\n\r\nvoid add_user(struct hash_entry *s) {\r\n HASH_ADD_INT(users, id, s);\r\n}\r\n</pre>\r\n</p>\r\n\r\n<p><b>2. Looking up an item in a hash:</b>\r\n<pre>\r\nstruct hash_entry *find_user(int user_id) {\r\n struct hash_entry *s;\r\n HASH_FIND_INT(users, &user_id, s);\r\n return s;\r\n}\r\n</pre>\r\n</p>\r\n\r\n<p><b>3. Deleting an item in a hash:</b>\r\n<pre>\r\nvoid delete_user(struct hash_entry *user) {\r\n HASH_DEL(users, user); \r\n}\r\n</pre>\r\n</p>"], "csharp": ["C#", "<p><a href=\"https://learn.microsoft.com/en-us/dotnet/csharp/whats-new/csharp-13\" target=\"_blank\">C# 13</a> with .NET 9 runtime</p>"], "javascript": ["JavaScript", "<p><code>Node.js 22.14.0</code>.</p>\r\n\r\n<p>Your code is run with <code>--harmony</code> flag, enabling <a href=\"http://node.green/\" target=\"_blank\">new ES6 features</a>.</p>\r\n\r\n<p><a href=\"https://lodash.com\" target=\"_blank\">lodash.js</a> library is included by default.</p>\r\n\r\n<p>For Priority Queue / Queue data structures, you may use 6.3.2 version of <a href=\"https://github.com/datastructures-js/priority-queue/tree/v6.3.2\" target=\"_blank\">datastructures-js/priority-queue</a> and 4.2.3 version of <a href=\"https://github.com/datastructures-js/queue/tree/v4.2.3\" target=\"_blank\">datastructures-js/queue</a> and 1.0.4 version of <a href=\"https://github.com/datastructures-js/deque/tree/v1.0.4\" target=\"_blank\">datastructures-js/deque</a>.</p>"], "ruby": ["Ruby", "<p><code>Ruby 3.2</code></p>\r\n\r\n<p>Some common data structure implementations are provided in the Algorithms module: https://www.rubydoc.info/github/kanwei/algorithms/Algorithms</p>"], "swift": ["Swift", "<p><code>Swift 6.0</code>.</p>\r\n\r\n<p>You may use the following packages:<br/>\r\n<a href=\"https://github.com/apple/swift-algorithms/tree/1.2.0\" target=\"_blank\">swift-algorithms 1.2.0</a><br/>\r\n<a href=\"https://github.com/apple/swift-collections/tree/1.1.4\" target=\"_blank\">swift-collections 1.1.4</a><br/>\r\n<a href=\"https://github.com/apple/swift-numerics/tree/1.0.2\" target=\"_blank\">swift-numerics 1.0.2</a></p>"], "golang": ["Go", "<p><code>Go 1.23</code></p>\r\n<p>Support <a href=\"https://pkg.go.dev/github.com/emirpasic/[email protected]\" target=\"_blank\">https://pkg.go.dev/github.com/emirpasic/[email protected]</a> and <a href=\"https://pkg.go.dev/github.com/emirpasic/gods/[email protected]\" target=\"_blank\">https://pkg.go.dev/github.com/emirpasic/gods/[email protected]</a> library.</p>"], "python3": ["Python3", "<p><code>Python 3.11</code>.</p>\r\n\r\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\"https://docs.python.org/3/library/array.html\" target=\"_blank\">array</a>, <a href=\"https://docs.python.org/3/library/bisect.html\" target=\"_blank\">bisect</a>, <a href=\"https://docs.python.org/3/library/collections.html\" target=\"_blank\">collections</a>. If you need more libraries, you can import it yourself.</p>\r\n\r\n<p>For Map/TreeMap data structure, you may use <a href=\"http://www.grantjenks.com/docs/sortedcontainers/\" target=\"_blank\">sortedcontainers</a> library.</p>"], "scala": ["Scala", "<p><code>Scala 3.3.1</code>.</p>"], "kotlin": ["Kotlin", "<p><code>Kotlin 2.1.10</code>.</p>"], "rust": ["Rust", "<p><code>Rust 1.85.0</code>. Your code will be compiled with <code>opt-level</code> 2.</p>\r\n\r\n<p>Supports <a href=\"https://crates.io/crates/rand\" target=\"_blank\">rand v0.8</a> and <a href=\"https://crates.io/crates/regex\" target=\"_blank\">regex\u00a0v1</a> and <a href=\"https://crates.io/crates/itertools\" target=\"_blank\">itertools\u00a0v0.14</a> from crates.io</p>"], "php": ["PHP", "<p><code>PHP 8.2</code>.</p>\r\n<p>With bcmath module</p>"], "typescript": ["Typescript", "<p><code>TypeScript 5.7.3, Node.js 22.14.0</code>.</p>\r\n\r\n<p>Compile Options: <code>--alwaysStrict --strictBindCallApply --strictFunctionTypes --target ES2024</code></p>\r\n\r\n<p><a href=\"https://lodash.com\" target=\"_blank\">lodash.js</a> library is included by default.</p>\r\n\r\n<p>For Priority Queue / Queue data structures, you may use 6.3.2 version of <a href=\"https://github.com/datastructures-js/priority-queue/tree/v6.3.2\" target=\"_blank\">datastructures-js/priority-queue</a> and 4.2.3 version of <a href=\"https://github.com/datastructures-js/queue/tree/v4.2.3\" target=\"_blank\">datastructures-js/queue</a> and 1.0.4 version of <a href=\"https://github.com/datastructures-js/deque/tree/v1.0.4\" target=\"_blank\">datastructures-js/deque</a>.</p>"], "racket": ["Racket", "<p><a href=\"https://docs.racket-lang.org/guide/performance.html#%28tech._c%29\" target=\"_blank\">Racket CS</a> v8.15</p>\r\n\r\n<p>Using <code>#lang racket</code></p>\r\n\r\n<p>Required <code>data/gvector data/queue data/order data/heap</code> automatically for your convenience</p>"], "erlang": ["Erlang", "Erlang/OTP 26"], "elixir": ["Elixir", "Elixir 1.17 with Erlang/OTP 26"], "dart": ["Dart", "<p>Dart 3.2. You may use package <a href=\"https://pub.dev/packages/collection/versions/1.18.0\" target=\"_blank\">collection</a></p>\r\n\r\n<p>Your code will be run directly without compiling</p>"]} | ['Hash Table', 'Math', 'String'] |
13 | Roman to Integer | roman-to-integer | <p>Roman numerals are represented by seven different symbols: <code>I</code>, <code>V</code>, <code>X</code>, <code>L</code>, <code>C</code>, <code>D</code> and <code>M</code>.</p>
<pre>
<strong>Symbol</strong> <strong>Value</strong>
I 1
V 5
X 10
L 50
C 100
D 500
M 1000</pre>
<p>For example, <code>2</code> is written as <code>II</code> in Roman numeral, just two ones added together. <code>12</code> is written as <code>XII</code>, which is simply <code>X + II</code>. The number <code>27</code> is written as <code>XXVII</code>, which is <code>XX + V + II</code>.</p>
<p>Roman numerals are usually written largest to smallest from left to right. However, the numeral for four is not <code>IIII</code>. Instead, the number four is written as <code>IV</code>. Because the one is before the five we subtract it making four. The same principle applies to the number nine, which is written as <code>IX</code>. There are six instances where subtraction is used:</p>
<ul>
<li><code>I</code> can be placed before <code>V</code> (5) and <code>X</code> (10) to make 4 and 9. </li>
<li><code>X</code> can be placed before <code>L</code> (50) and <code>C</code> (100) to make 40 and 90. </li>
<li><code>C</code> can be placed before <code>D</code> (500) and <code>M</code> (1000) to make 400 and 900.</li>
</ul>
<p>Given a roman numeral, convert it to an integer.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<strong>Input:</strong> s = "III"
<strong>Output:</strong> 3
<strong>Explanation:</strong> III = 3.
</pre>
<p><strong class="example">Example 2:</strong></p>
<pre>
<strong>Input:</strong> s = "LVIII"
<strong>Output:</strong> 58
<strong>Explanation:</strong> L = 50, V= 5, III = 3.
</pre>
<p><strong class="example">Example 3:</strong></p>
<pre>
<strong>Input:</strong> s = "MCMXCIV"
<strong>Output:</strong> 1994
<strong>Explanation:</strong> M = 1000, CM = 900, XC = 90 and IV = 4.
</pre>
<p> </p>
<p><strong>Constraints:</strong></p>
<ul>
<li><code>1 <= s.length <= 15</code></li>
<li><code>s</code> contains only the characters <code>('I', 'V', 'X', 'L', 'C', 'D', 'M')</code>.</li>
<li>It is <strong>guaranteed</strong> that <code>s</code> is a valid roman numeral in the range <code>[1, 3999]</code>.</li>
</ul>
| Easy | 4.7M | 7.3M | 4,677,244 | 7,260,584 | 64.4% | ['integer-to-roman'] | [] | Algorithms | [{"value": "cpp", "text": "C++", "defaultCode": "class Solution {\npublic:\n int romanToInt(string s) {\n \n }\n};"}, {"value": "java", "text": "Java", "defaultCode": "class Solution {\n public int romanToInt(String s) {\n \n }\n}"}, {"value": "python", "text": "Python", "defaultCode": "class Solution(object):\n def romanToInt(self, s):\n \"\"\"\n :type s: str\n :rtype: int\n \"\"\"\n "}, {"value": "python3", "text": "Python3", "defaultCode": "class Solution:\n def romanToInt(self, s: str) -> int:\n "}, {"value": "c", "text": "C", "defaultCode": "int romanToInt(char* s) {\n \n}"}, {"value": "csharp", "text": "C#", "defaultCode": "public class Solution {\n public int RomanToInt(string s) {\n \n }\n}"}, {"value": "javascript", "text": "JavaScript", "defaultCode": "/**\n * @param {string} s\n * @return {number}\n */\nvar romanToInt = function(s) {\n \n};"}, {"value": "typescript", "text": "TypeScript", "defaultCode": "function romanToInt(s: string): number {\n \n};"}, {"value": "php", "text": "PHP", "defaultCode": "class Solution {\n\n /**\n * @param String $s\n * @return Integer\n */\n function romanToInt($s) {\n \n }\n}"}, {"value": "swift", "text": "Swift", "defaultCode": "class Solution {\n func romanToInt(_ s: String) -> Int {\n \n }\n}"}, {"value": "kotlin", "text": "Kotlin", "defaultCode": "class Solution {\n fun romanToInt(s: String): Int {\n \n }\n}"}, {"value": "dart", "text": "Dart", "defaultCode": "class Solution {\n int romanToInt(String s) {\n \n }\n}"}, {"value": "golang", "text": "Go", "defaultCode": "func romanToInt(s string) int {\n \n}"}, {"value": "ruby", "text": "Ruby", "defaultCode": "# @param {String} s\n# @return {Integer}\ndef roman_to_int(s)\n \nend"}, {"value": "scala", "text": "Scala", "defaultCode": "object Solution {\n def romanToInt(s: String): Int = {\n \n }\n}"}, {"value": "rust", "text": "Rust", "defaultCode": "impl Solution {\n pub fn roman_to_int(s: String) -> i32 {\n \n }\n}"}, {"value": "racket", "text": "Racket", "defaultCode": "(define/contract (roman-to-int s)\n (-> string? exact-integer?)\n )"}, {"value": "erlang", "text": "Erlang", "defaultCode": "-spec roman_to_int(S :: unicode:unicode_binary()) -> integer().\nroman_to_int(S) ->\n ."}, {"value": "elixir", "text": "Elixir", "defaultCode": "defmodule Solution do\n @spec roman_to_int(s :: String.t) :: integer\n def roman_to_int(s) do\n \n end\nend"}] | "III" | {
"name": "romanToInt",
"params": [
{
"name": "s",
"type": "string"
}
],
"return": {
"type": "integer"
}
} | {"cpp": ["C++", "<p>Compiled with <code> clang 19 </code> using the latest C++ 23 standard, and <code>libstdc++</code> provided by GCC 14.</p>\r\n\r\n<p>Your code is compiled with level two optimization (<code>-O2</code>). <a href=\"https://github.com/google/sanitizers/wiki/AddressSanitizer\" target=\"_blank\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>"], "java": ["Java", "<p><code>OpenJDK 21</code>. Using compile arguments: <code>--enable-preview --release 21</code></p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>\r\n<p>Includes <code>Pair</code> class from https://docs.oracle.com/javase/8/javafx/api/javafx/util/Pair.html.</p>"], "python": ["Python", "<p><code>Python 2.7.18</code>.</p>\r\n\r\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\"https://docs.python.org/2/library/array.html\" target=\"_blank\">array</a>, <a href=\"https://docs.python.org/2/library/bisect.html\" target=\"_blank\">bisect</a>, <a href=\"https://docs.python.org/2/library/collections.html\" target=\"_blank\">collections</a>. If you need more libraries, you can import it yourself.</p>\r\n\r\n<p>For Map/TreeMap data structure, you may use <a href=\"http://www.grantjenks.com/docs/sortedcontainers/\" target=\"_blank\">sortedcontainers</a> library.</p>\r\n\r\n<p>Note that Python 2.7 <a href=\"https://www.python.org/dev/peps/pep-0373/\" target=\"_blank\">is not maintained anymore</a>. For the latest Python, please choose Python3 instead.</p>"], "c": ["C", "<p>Compiled with <code>gcc 14</code> using the gnu11 standard.</p>\r\n\r\n<p>Your code is compiled with level one optimization (<code>-O2</code>). <a href=\"https://github.com/google/sanitizers/wiki/AddressSanitizer\" target=\"_blank\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\r\n\r\n<p>Most standard library headers are already included automatically for your convenience.</p>\r\n\r\n<p>For hash table operations, you may use <a href=\"https://troydhanson.github.io/uthash/\" target=\"_blank\">uthash</a>. \"uthash.h\" is included by default. Below are some examples:</p>\r\n\r\n<p><b>1. Adding an item to a hash.</b>\r\n<pre>\r\nstruct hash_entry {\r\n int id; /* we'll use this field as the key */\r\n char name[10];\r\n UT_hash_handle hh; /* makes this structure hashable */\r\n};\r\n\r\nstruct hash_entry *users = NULL;\r\n\r\nvoid add_user(struct hash_entry *s) {\r\n HASH_ADD_INT(users, id, s);\r\n}\r\n</pre>\r\n</p>\r\n\r\n<p><b>2. Looking up an item in a hash:</b>\r\n<pre>\r\nstruct hash_entry *find_user(int user_id) {\r\n struct hash_entry *s;\r\n HASH_FIND_INT(users, &user_id, s);\r\n return s;\r\n}\r\n</pre>\r\n</p>\r\n\r\n<p><b>3. Deleting an item in a hash:</b>\r\n<pre>\r\nvoid delete_user(struct hash_entry *user) {\r\n HASH_DEL(users, user); \r\n}\r\n</pre>\r\n</p>"], "csharp": ["C#", "<p><a href=\"https://learn.microsoft.com/en-us/dotnet/csharp/whats-new/csharp-13\" target=\"_blank\">C# 13</a> with .NET 9 runtime</p>"], "javascript": ["JavaScript", "<p><code>Node.js 22.14.0</code>.</p>\r\n\r\n<p>Your code is run with <code>--harmony</code> flag, enabling <a href=\"http://node.green/\" target=\"_blank\">new ES6 features</a>.</p>\r\n\r\n<p><a href=\"https://lodash.com\" target=\"_blank\">lodash.js</a> library is included by default.</p>\r\n\r\n<p>For Priority Queue / Queue data structures, you may use 6.3.2 version of <a href=\"https://github.com/datastructures-js/priority-queue/tree/v6.3.2\" target=\"_blank\">datastructures-js/priority-queue</a> and 4.2.3 version of <a href=\"https://github.com/datastructures-js/queue/tree/v4.2.3\" target=\"_blank\">datastructures-js/queue</a> and 1.0.4 version of <a href=\"https://github.com/datastructures-js/deque/tree/v1.0.4\" target=\"_blank\">datastructures-js/deque</a>.</p>"], "ruby": ["Ruby", "<p><code>Ruby 3.2</code></p>\r\n\r\n<p>Some common data structure implementations are provided in the Algorithms module: https://www.rubydoc.info/github/kanwei/algorithms/Algorithms</p>"], "swift": ["Swift", "<p><code>Swift 6.0</code>.</p>\r\n\r\n<p>You may use the following packages:<br/>\r\n<a href=\"https://github.com/apple/swift-algorithms/tree/1.2.0\" target=\"_blank\">swift-algorithms 1.2.0</a><br/>\r\n<a href=\"https://github.com/apple/swift-collections/tree/1.1.4\" target=\"_blank\">swift-collections 1.1.4</a><br/>\r\n<a href=\"https://github.com/apple/swift-numerics/tree/1.0.2\" target=\"_blank\">swift-numerics 1.0.2</a></p>"], "golang": ["Go", "<p><code>Go 1.23</code></p>\r\n<p>Support <a href=\"https://pkg.go.dev/github.com/emirpasic/[email protected]\" target=\"_blank\">https://pkg.go.dev/github.com/emirpasic/[email protected]</a> and <a href=\"https://pkg.go.dev/github.com/emirpasic/gods/[email protected]\" target=\"_blank\">https://pkg.go.dev/github.com/emirpasic/gods/[email protected]</a> library.</p>"], "python3": ["Python3", "<p><code>Python 3.11</code>.</p>\r\n\r\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\"https://docs.python.org/3/library/array.html\" target=\"_blank\">array</a>, <a href=\"https://docs.python.org/3/library/bisect.html\" target=\"_blank\">bisect</a>, <a href=\"https://docs.python.org/3/library/collections.html\" target=\"_blank\">collections</a>. If you need more libraries, you can import it yourself.</p>\r\n\r\n<p>For Map/TreeMap data structure, you may use <a href=\"http://www.grantjenks.com/docs/sortedcontainers/\" target=\"_blank\">sortedcontainers</a> library.</p>"], "scala": ["Scala", "<p><code>Scala 3.3.1</code>.</p>"], "kotlin": ["Kotlin", "<p><code>Kotlin 2.1.10</code>.</p>"], "rust": ["Rust", "<p><code>Rust 1.85.0</code>. Your code will be compiled with <code>opt-level</code> 2.</p>\r\n\r\n<p>Supports <a href=\"https://crates.io/crates/rand\" target=\"_blank\">rand v0.8</a> and <a href=\"https://crates.io/crates/regex\" target=\"_blank\">regex\u00a0v1</a> and <a href=\"https://crates.io/crates/itertools\" target=\"_blank\">itertools\u00a0v0.14</a> from crates.io</p>"], "php": ["PHP", "<p><code>PHP 8.2</code>.</p>\r\n<p>With bcmath module</p>"], "typescript": ["Typescript", "<p><code>TypeScript 5.7.3, Node.js 22.14.0</code>.</p>\r\n\r\n<p>Compile Options: <code>--alwaysStrict --strictBindCallApply --strictFunctionTypes --target ES2024</code></p>\r\n\r\n<p><a href=\"https://lodash.com\" target=\"_blank\">lodash.js</a> library is included by default.</p>\r\n\r\n<p>For Priority Queue / Queue data structures, you may use 6.3.2 version of <a href=\"https://github.com/datastructures-js/priority-queue/tree/v6.3.2\" target=\"_blank\">datastructures-js/priority-queue</a> and 4.2.3 version of <a href=\"https://github.com/datastructures-js/queue/tree/v4.2.3\" target=\"_blank\">datastructures-js/queue</a> and 1.0.4 version of <a href=\"https://github.com/datastructures-js/deque/tree/v1.0.4\" target=\"_blank\">datastructures-js/deque</a>.</p>"], "racket": ["Racket", "<p><a href=\"https://docs.racket-lang.org/guide/performance.html#%28tech._c%29\" target=\"_blank\">Racket CS</a> v8.15</p>\r\n\r\n<p>Using <code>#lang racket</code></p>\r\n\r\n<p>Required <code>data/gvector data/queue data/order data/heap</code> automatically for your convenience</p>"], "erlang": ["Erlang", "Erlang/OTP 26"], "elixir": ["Elixir", "Elixir 1.17 with Erlang/OTP 26"], "dart": ["Dart", "<p>Dart 3.2. You may use package <a href=\"https://pub.dev/packages/collection/versions/1.18.0\" target=\"_blank\">collection</a></p>\r\n\r\n<p>Your code will be run directly without compiling</p>"]} | ['Hash Table', 'Math', 'String'] |
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in Data Studio
LeetCode Scraper Dataset
This dataset contains information scraped from LeetCode, including problem details, metadata, and related files. It is designed to assist developers in analyzing LeetCode problems, generating insights, and building tools for competitive programming or educational purposes.
questions_deets.csv
- Contains detailed information about each problem, including problem descriptions, constraints, and examples.
- Columns:
questionFrontendId: Unique problem ID.questionTitle: Title of the problem.content: HTML content of the problem description.difficulty: Problem difficulty.topicTags: Tags associated with the problem.codeDefinition: Code templates for various programming languages.TitleSlug: URL-friendly title for the problem. Construct the link this way: "https://leetcode.com/problems/{titleSlug}/description/"difficulty,totalAccepted,totalSubmission,totalAcceptedRaw,totalSubmissionRaw,acRatesimilarQuestions: Questions simmilar to current question.mysqlSchemas,category,sampleTestCase,metaData,envInfo.
This dataset is part of a broader collection of LeetCode-related datasets. It complements:
- LeetCode Problem Set – a lightweight dataset containing LeetCode problems along with titles, slugs, difficulty levels, and basic metadata (no content or solutions).
- LeetCode Problem Solutions – includes up to 100 of the most upvoted community solutions per problem, with full code, summaries, and metadata.
Note: New problems are added to the platform weekly. If you’d like the data refreshed or want more solutions per problem, feel free to reach out!
The scraper used to collect this data is open-sourced here: timetooth/leetcode_scraper. Give it a ⭐ if you find it helpful!
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