寒假4-前缀和

#include<iostream>
using namespace std;
int n, m;
int arr[10010];
int arrs[10010];
int main()
{
	cin >> n >> m;
	for (int i = 1;i <= n;i++)
	{
		cin >> arr[i];
		arrs[i] = arrs[i - 1]+arr[i];
	}
	int left, right;
	for (int i = 1;i <= m;i++)
	{
		cin >> left >> right;
		cout << arrs[right] - arrs[left];
	}
	return 0;
}

#include<iostream>
using namespace std;
int const N = 1010;
int arr[N][N];
int arrs[N][N];
int n, m, q;
int main()
{
	cin >> n >> m >> q;
	for (int i = 1;i <= n;i++)
	{
		for (int j = 1;j <= m;j++)
		{
			cin >> arr[i][j];
			arrs[i][j] = arr[i][j];
			if (i == 1)arrs[i][j] += arrs[i - 1][j];
			else if (j == 1)arrs[i][j] += arrs[i][j - 1];
			else
			{
				arrs[i][j] += arrs[i - 1][j];
				arrs[i][j] += arrs[i][j - 1];
				arrs[i][j] -= arrs[i - 1][j - 1];
			}
		}
	}
	int x1, x2, y1, y2;
	for (int i = 1;i <= q;i++)
	{
		cin >> x1 >> y1 >> x2 >> y2;
		cout << arrs[x2][y2] + arrs[x1-1][y1-1] - arrs[x1-1][y2] - arrs[x2][y1-1] << endl;
	}
	return 0;
}