HDU 1838 Chessboard

dp[i][j]表示以（i,j）为右下角所含棋盘的最大规模，

如果 s[i][j] == s[i-1][j-1] && s[i][j] != s[i-1][j] && s[i][j] != s[i][j-1]      dp[i][j] = min( dp[i-1][j-1], dp[i-1][j], dp[i][j-1]) + 1

否则dp[i][j] = 1

 //#define LOCAL
 #include <iostream>
 #include <cstdio>
 #include <cstring>
 #include <algorithm>
 using namespace std;

 int const maxn =  + ;
 char map[maxn][maxn];
 int dp[maxn][maxn];

 int main(void)
 {
     #ifdef LOCAL
         freopen("1838in.txt", "r", stdin);
     #endif

     int T;
     scanf("%d", &T);
     while(T--)
     {
         int n;
         scanf("%d", &n);
         int i, j;
         for(i = ; i < n; ++i)
             scanf("%s", map[i]);
         for(i = ; i < n; ++i)
             dp[][i] = dp[i][] = ;
         int size = , cnt = ;
         for(i = ; i < n; ++i)
             for(j = ; j < n; ++j)
             {
                 if(map[i][j] == map[i-][j-] && map[i][j] != map[i-][j]
                     && map[i][j] != map[i][j-])
                     dp[i][j] = min(min(dp[i][j-], dp[i-][j]), dp[i-][j-]) + ;
                 else dp[i][j] = ;
                 if(map[i][j] == '')
                     size = max(size, dp[i][j]);
             }

         for(i = ; i < n; ++i)
             for(j = ; j < n; ++j)
                 if(dp[i][j] == size && map[i][j] == '')
                     ++cnt;
         printf("%d %d\n", size, cnt);
     }
     return ;
 }

代码君