HDU 4618 Palindrome Sub-Array(DP)

题目链接

我还是图样啊....比赛的时候没敢暴力去搜...

 #include <cstdio>
 #include <cstdlib>
 #include <cstring>
 #include <map>
 #include <ctime>
 #include <cmath>
 using namespace std;
 #define LL __int64
 char dp[][][];
 int p[][];
 int n,m;
 int dfs(int x,int y,int step)
 {
     int i,j,k;
     if(step == )
     return ;
     else if(step == )
     return ;
     if(x > n||y > m)
     return ;
     if(dp[x][y][step] == )
     return ;
     else if(dp[x][y][step] == )
     return ;
     int flag = ;
     for(i = x,j = x+step-,k = ;k <= step/&&flag;i ++,j --,k ++)
     {
         if(p[i][y] == p[j][y]&&p[i][y] == p[i][y+step-])
         ;
         else
         flag = ;
     }
     for(i = y,j = y+step-,k = ;k <= step/&&flag;i ++,j --,k ++)
     {
         if(p[x][i] == p[x][j]&&p[x][i] == p[x+step-][i])
         ;
         else
         flag = ;
     }
     if(flag == )
     {
         dp[x][y][step] = ;
         return ;
     }
     else if(flag)
     {
         return dp[x+][y+][step-] = dfs(x+,y+,step-);
     }
     return ;
 }
 int main()
 {
     int t,i,j,k,flag;
     scanf("%d",&t);
     while(t--)
     {
         scanf("%d%d",&n,&m);
         memset(dp,,sizeof(dp));
         for(i = ;i <= n;i ++)
         {
             for(j = ;j <= m;j ++)
             {
                 scanf("%d",&p[i][j]);
             }
         }
         flag = ;
         for(i = min(n,m);i >= &&flag;i --)
         {
             for(j = ;j <= n-i+&&flag;j ++)
             {
                 for(k = ;k <= m-i+&&flag;k ++)
                 {
                     if(dfs(j,k,i) == )
                     flag = ;
                 }
             }
             if(!flag) break;
         }
         printf("%d\n",i);
     }
     return ;
 }