poj2352 Stars

#include<iostream>
using namespace std;
#define MAXN 32001
int c[MAXN],num[MAXN];

int lowbit(int x)
{
return x&(x^(x-1));
}

void add(int t,int num)
{
while(t <= MAXN)
{
c[t] += num;
t += lowbit(t);
}
}

int getSum(int t)
{
int sum = 0;
while(t > 0)
{
sum += c[t];
t -= lowbit(t);
}
return sum;
}

int main()
{
int x,y,N;
scanf("%d",&N);
memset(c,0,sizeof(c));
memset(num,0,sizeof(num));

for(int i = 1;i<=N;i++)
{
scanf("%d%d",&x,&y);
x++;
num[getSum(x)]++;
add(x,1);
}
//按y排好序的，y相同时按x排好序
//对每个输入只要求出前面x比自己小的即可

for(int i = 0;i<N;i++)
printf("%d\n",num[i]);

return 0;
}