HOJ Stars 2678

这个题与poj的思路有点类似 点击打开poj Stars

#include 
#include 
#include 

using namespace std;

const int MAXN = 1010;
int c[MAXN][MAXN];

struct Node
{
	int x, y, z;
}stars[15010];

int cmp(Node a, Node b)
{
	if(a.z != b.z)
		return a.z < b.z;
	else if(a.y != b.y)
		return a.y < b.y;
	return a.x < b.x;
}

int lowbit( int x )
{
	return x&(-x);
}

void UFset(int x, int y, int data)
{
	for(int i = x; i < MAXN; i += lowbit(i))
		for(int j = y; j < MAXN; j += lowbit(j))
			c[i][j] += data;
}

int GetSum(int x, int y)
{
	int sum = 0;
	for(int i = x; i > 0; i -= lowbit(i))
		for(int j = y; j > 0; j -= lowbit(j))
			sum += c[i][j];
	return sum;
}


int main()
{
	int N;
	int i, x, y, z;
	int s[15010];
	while(scanf("%d", &N) != EOF)
	{
		memset(stars, 0, sizeof(stars));
		memset(c, 0, sizeof(c));
		memset(s, 0, sizeof(s));
		for(i = 0; i < N; ++i)
		{
			scanf("%d %d %d", &x, &y, &z);
			stars[i].x = x, stars[i].y = y, stars[i].z = z;
		}
		sort(stars, stars+N, cmp);
		for(i = 0; i < N; ++i)
		{
			int level = GetSum(stars[i].x+1, stars[i].y+1);//之所以要加1，那是因为可能有星星的坐标重复
			s[level]++;
			UFset(stars[i].x+1, stars[i].y+1, 1);
		}
		for(i = 0; i < N-1; ++i)
			printf("%d ", s[i]);
		printf("%d\n", s[i]);
	}
	return 0;
}