题解 | 【模板】二维前缀和

#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
const int N = 1010;
ll n,m,q,s[N][N];

int main(){
    cin>>n>>m>>q;
    for(int i = 1;i<=n;i++){
        for(int j = 1;j<=m;j++){
            cin>>s[i][j];
            s[i][j] +=  s[i-1][j] + s[i][j-1] - s[i-1][j-1];
        }
    }

    while(q--){
        int x1,y1,x2,y2;
        cin>>x1>>y1>>x2>>y2;
        ll num = s[x2][y2] - s[x1-1][y2] - s[x2][y1-1] + s[x1-1][y1-1];
        cout<<num<<"\n";
    }

    return 0;
}