AcWing 796. 子矩阵的和

Posted 2020-12-19 wisexu

AcWing 796. 子矩阵的和

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#include <bits/stdc++.h>
using namespace std;
const int N=1e3+10;
int a[N][N],S[N][N];
int main(){
    int n,m,q;
    scanf("%d%d%d",&n,&m,&q);
    for(int i=1;i<=n;i++)
        for(int j=1;j<=m;j++)
            scanf("%d",&a[i][j]);
    for(int i=1;i<=n;i++)
        for(int j=1;j<=m;j++)
            S[i][j]=S[i-1][j]+S[i][j-1]-S[i-1][j-1]+a[i][j];
    while(q--){
        int x1,y1,x2,y2;
        scanf("%d%d%d%d",&x1,&y1,&x2,&y2);
        cout<<S[x2][y2]-S[x1-1][y2]-S[x2][y1-1]+S[x1-1][y1-1]<<endl;
    }        
    return 0;
}