HDU-1541 POJ-2352 Stars

#include <iostream>
#include <cstring>
#define pb push_back
#define _for(i,a,b) for(int i = (a);i < (b);i ++)
#define INF 0x3f3f3f3f
#define sz size()

using namespace std;
typedef long long ll;

const int maxn = 1 << 18;

int n, dat[2*maxn];

void init(int n_)
{
    n = (1 << 18)-2;
    memset(dat,0,sizeof(dat));
}

//更新第k(0-index)个值为a
void update(int k)
{
    k += n+1;
    dat[k] ++;
    while(k>0)
    {
        k = (k-1)/2;
        dat[k] = dat[k*2+1]+dat[k*2+2];
    }
}

//求(a,b)val
//query(a,b,0,0,n)
int query(int a,int b,int k,int l,int r)
{
    //不相交
    if(r<a || b<l) return 0;

    if(a<=l && r<=b) {return dat[k];}
    else
    {
        int vl = query(a,b,k*2+1,l,(l+r)/2);
        int vr = query(a,b,k*2+2,(l+r)/2+1,r);
        
        return vl+vr;
    }
    return -1;//error
}

int readint()
{
    int t;
    scanf("%d",&t);
    return t;
}

int main()
{
    int N;
    while(scanf("%d",&N)!=EOF)
    {
        init(n);
        int rnt[15002];
        memset(rnt,0,sizeof(rnt));
        _for(i,0,N)
        {
            int x = readint();
            rnt[query(0,x,0,0,n)] ++;
            update(x);
            readint();
        }
        _for(i,0,N)
            printf("%d\n",rnt[i]);
    }
    return 0;
}