AcWing 796. 子矩阵的和

#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;}