题目链接：

 

#include
    
     #include
     
      #define max(a,b) a>b?a:bint d[1005][1005];int main(){    int T,n,m,x,y,i,j;    scanf("%d",&T);    while(T--)    {        scanf("%d%d%d%d",&n,&m,&x,&y);        memset(d,0,sizeof(d));        int maxx = -1;        for(i = 1 ; i <= n ; i ++)         for(j = 1 ; j <= m ; j ++)         {             scanf("%d",&d[i][j]);             d[i][j] += d[i - 1][j] + d[i][j - 1] - d[i - 1][j - 1];//d[i][j]表示这个点之前所有点的和             if(i >= x && j >= y)               maxx = max(maxx,d[i][j] - d[i - x][j] - d[i][j - y] + d[i - x][j - y]);         }        printf("%d\n",maxx);    }    return 0;}