백준 16507번 어두운 건 무서워 C++

https://www.acmicpc.net/problem/16507

16507번: 어두운 건 무서워

 

누적합

 

#include <iostream>
#include <string>
#include <vector>
#include <math.h>
#include <algorithm>
#include <utility>
#include <stack>
#include <queue>
#include <math.h>
#include <set>
#include <map>
#include <list>
#include <unordered_map>
#include <unordered_set>
#include <iomanip>
#include <limits.h>

using namespace std;
using int64 = long long;

int r, c, q;
vector<vector<int>> accSum;

int main() {
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	cout.tie(NULL);

	cin >> r >> c >> q;
	accSum = vector<vector<int>>(r + 1, vector<int>(c + 1, 0));
	for (int i = 1; i <= r; i++) {
		int sum = 0;
		for (int j = 1; j <= c; j++) {
			int k;
			cin >> k;
			sum += k;
			accSum[i][j] = sum;
		}
	}
	for (int i = 0; i < q; i++) {
		int r1, c1, r2, c2;
		cin >> r1 >> c1 >> r2 >> c2;
		int cnt = (r2 - r1 + 1) * (c2 - c1 + 1);
		int sum = 0;
		for (int j = r1; j <= r2; j++) {
			sum += accSum[j][c2] - accSum[j][c1 - 1];
		}
		cout << sum / cnt << "\n";
	}
};