题解 | #【模板】二维前缀和#

#include <iostream>
using namespace std;
const int N = 1010;
long long a[N][N], s[N][N];
int main() {
    int n, m, q;
    cin >> n >> m >> q;
    for(int i = 1; i <= n; i ++)
        for(int j = 1; j <= m; j ++)
            cin >> 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;
        cin >> x1 >> y1 >> x2 >> y2;
        long long res = 0;
        res = s[x2][y2] - s[x1 - 1][y2] - s[x2][y1 - 1] + s[x1 - 1][y1 - 1];
        cout << res << endl;
    }
}
// 64 位输出请用 printf("%lld")