蓝桥杯省赛 棋盘 3533 二维差分+二维前缀和

传送门 0棋盘 - 蓝桥云课

const int N = 2e3 + 10;


int n,m;
int a[N][N];

void insert(int x11,int y11,int x22,int y22)
{
	a[x11][y11] ++;
	a[x11][y22 + 1] --;
	a[x22 + 1][y11] --;
	a[x22 + 1][y22 + 1] ++;
}

void solve()
{
	cin >> n >> m;
	for (int i = 1;i <= m;i ++)
	{
		int x11,y11,x22,y22;
		cin >> x11 >> y11 >> x22 >> y22;
		insert(x11,y11,x22,y22);
	}	
	
	for (int i = 1;i <= n;i ++)
		for (int j = 1;j <= m;j ++)
			a[i][j] += a[i - 1][j] + a[i][j - 1] - a[i - 1][j - 1];
			
	for (int i = 1;i <= n;i ++)
	{
		for (int j = 1;j <= m;j ++)
		{
			if (a[i][j] & 1) cout << 1;//加了奇数次,为黑子
			else cout << 0;//偶数次，为白子
		}
		cout << endl;
	}
			
}