树状数组Hdu1541

#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <algorithm>
#include <cmath>
#include <stack>
#include <queue>
#include <vector>
#include <map>
#include <string>
#include <iostream>
using namespace std;
int a[222222];
int ret[222222];
const int Max=33000;
int lowbit(int x)
{
    return x&(-x);
}

int ask(int k)
{
    int sum=0;
    while(k>0){
        sum+=a[k];
        k-=lowbit(k);
    }
    return sum;
}

void change(int x,int add)
{
    while(x<=Max){
        a[x]+=add;
        x+=lowbit(x);
    }
}

int main()
{
    int n,x,y;
    while(scanf("%d",&n)!=EOF){
        memset(a,0,sizeof(a));
        memset(ret,0,sizeof(ret));
        for(int i=0;i<n;i++){
            scanf("%d%d",&x,&y);
            change(x+1,1);
            int ans=ask(x+1)-1;
            ret[ans]++;
        }
        for(int i=0;i<n;i++)
            printf("%d
",ret[i]);
    }
    return 0;
}

  

原文地址:https://www.cnblogs.com/yigexigua/p/3773716.html