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#include <bits/stdc++.h> |
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using namespace std; |
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const int MAXN = 100; |
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struct coordinate { |
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double x, y; |
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} point[MAXN+2]; |
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double distance( double x1, double y1, double x2, double y2 ) { |
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return ( sqrt( (x1 - x2)*(x1 - x2) + (y1 - y2)*(y1 - y2) ) ); |
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} |
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struct data { |
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int x, y; |
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double cost; |
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bool operator < (const data &temp ) const { |
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return (cost < temp.cost); |
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} |
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}; |
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vector <data> edge; |
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int pr[MAXN+2]; |
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int findParent( int node ) { |
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return ( (pr[node] == node) ? node : findParent( pr[node] ) ); |
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} |
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double mst( int n ) { |
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sort( edge.begin(), edge.end() ); |
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for( int i = 0 ; i <= MAXN ; ++i ) pr[i] = i; |
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double cost = 0.0; |
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int counter = 0; |
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for( int i = 0 ; i < edge.size() ; ++i ) { |
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int x = findParent( edge[i].x ); |
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int y = findParent( edge[i].y ); |
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if( x != y ) { |
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pr[x] = y; |
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++counter; |
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cost += edge[i].cost; |
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if( counter == (n - 1) ) break; |
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} |
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} |
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return cost; |
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} |
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int main( int argc, char ** argv ) { |
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int T; |
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scanf( "%d", &T ); |
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for( int nCase = 1 ; nCase <= T ; ++nCase ) { |
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int n; |
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scanf( "%d", &n ); |
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for( int i = 1 ; i <= n ; ++i ) scanf( "%lf %lf", &point[i].x, &point[i].y ); |
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for( int i = 0 ; i <= n ; ++i ) edge.clear(); |
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for( int i = 1 ; i <= n ; ++i ) |
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for( int j = i + 1 ; j <= n ; ++j ) { |
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double c = distance( point[i].x, point[i].y, point[j].x, point[j].y ); |
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data get; |
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get.x = i, get.y = j, get.cost = c; |
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edge.push_back( get ); |
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get.x = j, get.y = i, get.cost = c; |
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edge.push_back( get ); |
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} |
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if( nCase != 1 ) puts( "" ); |
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printf( "%0.2lf\n", mst( n ) ); |
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} |
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return 0; |
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} |
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