CF 22B. Bargaining Table

水题。好久没有写过优化搜索题了。

 #include <cstdio>
 #include <cstring>
 #include <iostream>
 #include <vector>
 using namespace std;
 char str[][];
 int r[][];
 int c[][];
 int judge(int rx,int ry,int lx,int ly)
 {
     int i,j;
     for(i = lx;i <= rx;i ++)
     {
         for(j = ly;j <= ry;j ++)
         {
             if(str[i-][j-] == '')
             return ;
         }
     }
     return ;
 }
 int main()
 {
     int n,m,i,j,k,u,ans;
     scanf("%d%d",&n,&m);
     for(i = ;i < n;i ++)
     scanf("%s",str[i]);
     ans = ;
     for(i = ;i <= n;i ++)
     {
         for(j = ;j <= m;j ++)
         {
            if(str[i-][j-] == '')
            {
                r[i][j] = r[i-][j] + ;
                c[i][j] = c[i][j-] + ;
            }
            else
            {
                r[i][j] = ;
                c[i][j] = ;
            }
         }
     }
     for(i = n;i >= ;i --)
     {
         for(j = m;j >= ;j --)
         {
             for(k = ;k <= r[i][j];k ++)
             {
                 for(u = ;u <= c[i][j];u ++)
                 {
                     if(ans >= (k+u)*) continue;
                     if(judge(i,j,i-k+,j-u+))
                     {
                         ans = max(ans,(k+u)*);
                     }
                 }
             }
         }
     }
     printf("%d\n",ans);
     return ;
 }