30天学会基础算法 (地毯—前缀和) ^2^

题目链接

题目描述

输入格式

输出格式

输入样例

5 3
2 2 3 3
3 3 5 5
1 2 1 4

输出样例

0 1 1 1 0
0 1 1 0 0
0 1 2 1 1
0 0 1 1 1
0 0 1 1 1

样例解释

• 覆盖第一个地毯后：

0 0 0 0 0
0 1 1 0 0
0 1 1 0 0 
0 0 0 0 0 
0 0 0 0 0 

• 覆盖第二个地毯后：

 0 0 0 0 0
0 1 1 0 0
0 1 2 1 1 
0 0 1 1 1 
0 0 1 1 1

• 覆盖第三个地毯后：

0 1 1 1 0
0 1 1 0 0
0 1 2 1 1
0 0 1 1 1
0 0 1 1 1

• code

#include<iostream>
using namespace std;
int n, m;
int f[1010][1010];
int a[1010][1010];
int main()
{
	cin >> n >> m;
	int x1, x2, y1, y2;
	for (int i = 1; i <= m; i++)
	{
		cin >> x1 >> y1 >> x2 >> y2;
		for (int j = x1; j <= x2; j++)
			for (int k = y1; k <= y2; k++)
				f[j][k]++;
	}
	for (int i = 1; i <= n; i++)
	{
		for (int j = 1; j <= n; j++)
			cout << f[i][j] << " ";
		cout << endl;
	}
	return 0;
}