1
4 5 2 2
3 361 649 676 588
992 762 156 993 169
662 34 638 89 543
525 165 254 809 280

2474

#include<stdio.h>
#include<string.h>
int a[1001][1001];
int dp[1001];
int main(){
	int t,n,m,x,y,i,j,maxn;
	scanf("%d",&t);
	while(t--){
		scanf("%d%d%d%d",&m,&n,&x,&y);
		for(i=1;i<=m;++i){
			for(j=1;j<=n;++j){
				scanf("%d",&a[i][j]);
				a[i][j]=a[i][j]+a[i-1][j];    //此处
			}
		}
		maxn=-1;
		for(i=x;i<=m;++i){
			memset(dp,0,sizeof(dp));
			for(j=1;j<=m;++j){
				dp[j]=a[i][j]-a[i-x][j];  //
				dp[j]=dp[j]+dp[j-1];
				if(maxn<dp[j]-dp[j-y]&&j>=y)
				   maxn=dp[j]-dp[j-y];
			}
		}
		printf("%d\n",maxn);
	}
	return 0;
}