题解 | #【模板】二维前缀和#

#include <iostream>
#include <vector>

using namespace std;

int main()
{
    int n, m, q;
    cin >> n >> m >> q;
    vector<vector<int>> nums(n + 1, vector<int>(m + 1));
    vector<vector<long long>> dp(n + 1, vector<long long>(m + 1));

    for(int i = 1; i <= n;i++)
        for(int j = 1; j <= m;j++)
            cin >> nums[i][j];
    for(int i = 1; i <= n;i++)
        for(int j = 1; j <= m;j++)
            dp[i][j] = dp[i-1][j] + dp[i][j-1] + nums[i][j] - dp[i-1][j-1];
    while(q--)
    {
        int x1, y1, x2,y2;
        cin >> x1 >> y1 >> x2 >> y2;
        cout << dp[x2][y2] - dp[x1-1][y2] - dp[x2][y1-1] + dp[x1-1][y1-1] << endl;
    }


}