POJ2155 Matrix 二维树状数组

神一般的二维区间更新，运用二维树状数组会有神奇的效果。更改四个角实现区间更改的效果实在是太神奇了。。

#pragma warning(disable:4996)
#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
#include<vector>
#include<cmath>
#define maxn 1000
using namespace std;

int bit[maxn + 50][maxn + 50];
int n;

void inc(int i, int j,int m)
{
	for (; i <= n; i += i&(-i)){
		for (int tmpj = j; tmpj <= n; tmpj += (tmpj&(-tmpj)))
			bit[i][tmpj] += m;
	}
}

int get(int i, int j)
{
	int sum = 0;
	for (; i > 0; i -= i&-i){
		for (int tmpj = j; tmpj > 0; tmpj -= tmpj&-tmpj)
			sum += bit[i][tmpj];
	}
	return sum;
}
int q;
int main()
{
	int T; cin >> T;
	while (T--)
	{
		memset(bit, 0, sizeof(bit));
		scanf("%d%d", &n, &q);
		char str[3]; int x1, y1, x2, y2;
		for (int i = 0; i < q; i++)
		{
			scanf("%s",str);
			if (str[0] == 'C'){
				scanf("%d%d%d%d", &x1, &y1, &x2, &y2);
				x2++; y2++;
				inc(x1, y1,1); inc(x2, y2,1); inc(x1, y2,-1); inc(x2, y1,-1);
			}
			else{
				scanf("%d%d", &x1, &y1);
				printf("%d
", get(x1, y1) & 1);
			}
		}
		if (T) puts("");
	}
	return 0;
}