HDU 1559 最大子矩阵

http://acm.hdu.edu.cn/showproblem.php?pid=1559

#include<iostream>using namespace std;#define N 1001int dp[N][N];int main(void){int t;int n,m,x,y;scanf("%d",&t);while(t--){scanf("%d%d",&n,&m);scanf("%d%d",&x,&y);memset(dp,0,sizeof(int)*n*m);int M=INT_MIN;for(int i=1;i<=n;i++)for(int j=1;j<=m;j++){scanf("%d",&dp[i][j]);dp[i][j]+=dp[i-1][j]+dp[i][j-1]-dp[i-1][j-1];if(i>=x&&j>=y){int temp=dp[i][j]-dp[i-x][j]-dp[i][j-y]+dp[i-x][j-y];if(temp>M)M=temp;}}printf("%d/n",M);}} 

dp[i][j]代表到这个点之前所有数的和！