【树状数组】 poj2352 Stars

#include<cstdio>
#include<cstring>
using namespace std;
int a[15005],c[32010];
#define lowbit(x) ((x)&(-(x)))
void update(int pos,int value) //更新pos的值
{
int x=pos;
for(;x<=32005;x+=lowbit(x))
c[x]+=value;
}
int getsum(int pos)//求1到pos位置的和
{
int x=pos,sum=0;
for(;x>0;x-=lowbit(x))
sum+=c[x];
return sum;
}
int main()
{
int x,y,n;
for(;~scanf("%d",&n);)
{
memset(c,0,sizeof(c));
memset(a,0,sizeof(a));
for(int i=0;i<n;++i)
{
scanf("%d%d",&x,&y);
a[getsum(x+1)]++;
update(x+1,1);
}
for(int i=0;i<n;++i)
printf("%d\n",a[i]);
}
return 0;
}