#include using namespace std; char a[51][51]; int dp[51][51]={}; int h,w; int dr[8] = {-1,-1,-1,0,0,1,1,1,}; int dc[8] = {-1,1,0,-1,1,-1,1,0}; int dfs(int r, int c){ if(dp[r][c]!=0) return dp[r][c]; for(int i=0;i<8;i++){ if(r+dr[i]<0||c+dc[i]<0||r+dr[i]>=h||c+dc[i]>=w) continue; if((int)(a[r+dr[i]][c+dc[i]]-a[r][c])==1) dp[r][c]=max(dp[r][c], 1+dfs(r+dr[i],c+dc[i])); } return dp[r][c]; } int main(){ int t=1,ans=0,base=0; cin>>h>>w; while(h!=0&&w!=0){ base=0; ans=0; memset(dp,0,sizeof(dp)); for(int i=0;i>a[i][j]; } } for(int i=0;i>h>>w; } }