2167번: 2차원 배열의 합

#include<cstdio>
int main()
{
    int num[301][301], n, m, i, j, x, y, ans = 0;
    scanf("%d %d", &n, &m);
    for (int i = 1; i <= n; ++i)
        for (int j = 1; j <= m; ++j)
            scanf("%d", &num[i][j]);
    for (scanf("%d", &n); n--; ans = 0)
    {
        scanf("%d %d %d %d", &i, &j, &x, &y);
        for (int ii = i; ii <= x; ++ii)
            for (int jj = j; jj <= y; ++jj)
                ans += num[ii][jj];
        printf("%d\n", ans);
    }
}