Buy Tickets

Fast Arrangement

线段树倒序处理

Railway tickets were difficult to buy around the Lunar New Year in China, so we must get up early and join a long queue…

The Lunar New Year was approaching, but unluckily the Little Cat still had schedules going here and there. Now, he had to travel by train to Mianyang, Sichuan Province for the winter camp selection of the national team of Olympiad in Informatics.

It was one o’clock a.m. and dark outside. Chill wind from the northwest did not scare off the people in the queue. The cold night gave the Little Cat a shiver. Why not find a problem to think about? That was none the less better than freezing to death!

People kept jumping the queue. Since it was too dark around, such moves would not be discovered even by the people adjacent to the queue-jumpers. “If every person in the queue is assigned an integral value and all the information about those who have jumped the queue and where they stand after queue-jumping is given, can I find out the final order of people in the queue?” Thought the Little Cat.

Input
There will be several test cases in the input. Each test case consists of N + 1 lines where N (1 ≤ N ≤ 200,000) is given in the first line of the test case. The next N lines contain the pairs of values Posi and Vali in the increasing order of i (1 ≤ i ≤ N). For each i, the ranges and meanings of Posi and Vali are as follows:

Posi ∈ [0, i − 1] — The i-th person came to the queue and stood right behind the Posi-th person in the queue. The booking office was considered the 0th person and the person at the front of the queue was considered the first person in the queue.
Vali ∈ [0, 32767] — The i-th person was assigned the value Vali.
There no blank lines between test cases. Proceed to the end of input.

Output
For each test cases, output a single line of space-separated integers which are the values of people in the order they stand in the queue.

Sample Input

4
0 77
1 51
1 33
2 69
4
0 20523
1 19243
1 3890
0 31492

Sample Output

77 33 69 51
31492 20523 3890 19243

Hint
The figure below shows how the Little Cat found out the final order of people in the queue described in the first test case of the sample input.
在这里插入图片描述

#include<cstdio>
using namespace std;
const int maxn=200005;
struct node{
	int l,r,sum;
}tr[maxn<<2];
int q[maxn],a[maxn],b[maxn];
void pushup(int m)
{
	tr[m].sum=tr[m<<1].sum+tr[m<<1|1].sum;
}
void build(int m,int l,int r){
	tr[m].l=l;
	tr[m].r=r;
	if(l==r){
		tr[m].sum=1;
		return ;
	}
	int mid=(l+r)>>1;
	build(m<<1,l,mid);
	build(m<<1|1,mid+1,r);
	pushup(m);
}
void updata(int m,int p,int val){
	if(tr[m].l==tr[m].r){
		tr[m].sum=0;
		q[tr[m].l]=val;
		//printf("%d->%d ",tr[m].l,q[tr[m].l]);*/
		return ;
	}
	if(p<=tr[m<<1].sum)
	updata(m<<1,p,val);
	else
	updata(m<<1|1,p-tr[m<<1].sum,val);
	pushup(m);
}
int main(){
	int n;
	while(scanf("%d",&n)!=EOF){			
		for(int i=n;i>=1;--i){
			scanf("%d%d",&a[i],&b[i]);
			a[i]++;
		}
		build(1,1,n);
		for(int i=1;i<=n;++i){
		    updata(1,a[i],b[i]);
		}
		/*
		for(int i=1;i<=n;++i){
			if(i>1) printf(" ");
		    printf("%d",q[i]);
		}		
		printf("\n");
		*/
		for(int i=1;i<n;++i)
		printf("%d ",q[i]);
		printf("%d\n",q[n]);
	}
	return 0;
}

编写C程序实现如下功能:有 n 个人前来排队买票,其中第 0 人站在队伍 最前方,第 (n - 1) 人站在队伍最后方。 给你一个下标从 0 开始的整数数组 tickets ,数组长度为 n ,其中第 i 人想要购买的票数为 tickets[i] 。 每个人买票都需要用掉恰好 1 分 。一个人一次只能买一张票,如果需要购买更多票,他必须走到队尾重新排队(瞬间 发生,不计时间)。如果一个人没有剩下需要买的票,那他将会 离开队伍。 返回位于位置 k(下标从 0 开始)的人完成买票需要的时间(以分为单位)。 编写函数实现该功能,函数原型为: int buyTickets(int* tickets, int n, int k); tickets:购票队列数组,(下标从 0 开始) n:购票人数,即数组的元素个数; k:需要计算购票时间的位置(下标从 0 开始) 函数返回值:第k个人的购票时间;如果发生异常情况,返回-1; 只需要提交函数和相应的编译预处理命令; 人数n不超过20;每人购买的票数不超过20,且每人至少买1张车票; 示例 1: 输入:tickets = [2,3,2], k = 2 输出:6 解释: - 第一轮,队伍中的每个人都买到一张票,队伍变为 [1, 2, 1] 。 - 第二轮,队伍中的每个都又都买到一张票,队伍变为 [0, 1, 0] 。 位置 2 的人成功买到 2 张票,用掉 3 + 3 = 6 。 示例 2: 输入:tickets = [5,1,1,1], k = 0 输出:8 解释: - 第一轮,队伍中的每个人都买到一张票,队伍变为 [4, 0, 0, 0] 。 - 接下来的 4 轮,只有位置 0 的人在买票。 位置 0 的人成功买到 5 张票,用掉 4 + 1 + 1 + 1 + 1 = 8 。
最新发布
06-22
评论 1
添加红包

请填写红包祝福语或标题

红包个数最小为10个

红包金额最低5元

当前余额3.43前往充值 >
需支付:10.00
成就一亿技术人!
领取后你会自动成为博主和红包主的粉丝 规则
hope_wisdom
发出的红包
实付
使用余额支付
点击重新获取
扫码支付
钱包余额 0

抵扣说明:

1.余额是钱包充值的虚拟货币,按照1:1的比例进行支付金额的抵扣。
2.余额无法直接购买下载,可以购买VIP、付费专栏及课程。

余额充值