POJ 2352 starts 树状数组

#include <iostream>
#include<stdio.h>
#include<string.h>
using namespace std;
int N;
int x,y;
int tree[33000];
int level[16000];
int lowbit(int t){return t&(-t);}
void update(int index)
{
	while(index<33000)
	{
		tree[index]++;
		index+=lowbit(index);
	}
}
int getSum(int index)
{
	int sum=0;
	while(index>0)
	{
		sum+=tree[index];
		index-=lowbit(index);
	}
	return sum;
}
int main()
{
	setbuf(stdout,NULL);
	while(scanf("%d",&N)!=EOF)
	{
		int i;
		memset(tree,0,sizeof(tree));
		memset(level,0,sizeof(level));
		for(i=0;i<N;i++)
		{
			scanf("%d %d",&x,&y);
			x++;
			level[getSum(x)]++;
			update(x);
		}
		for(i=0;i<N;i++)
		{
			printf("%d\n",level[i]);
		}
	}
	return 0;
}