C - Twins(贪心)
Problem description
Imagine that you have a twin brother or sister. Having another person that looks exactly like you seems very unusual. It's hard to say if having something of an alter ego is good or bad. And if you do have a twin, then you very well know what it's like.
Now let's imagine a typical morning in your family. You haven't woken up yet, and Mom is already going to work. She has been so hasty that she has nearly forgotten to leave the two of her darling children some money to buy lunches in the school cafeteria. She fished in the purse and found some number of coins, or to be exact, ncoins of arbitrary values a1, a2, ..., an. But as Mom was running out of time, she didn't split the coins for you two. So she scribbled a note asking you to split the money equally.
As you woke up, you found Mom's coins and read her note. "But why split the money equally?" — you thought. After all, your twin is sleeping and he won't know anything. So you decided to act like that: pick for yourself some subset of coins so that the sum of values of your coins is strictly larger than the sum of values of the remaining coins that your twin will have. However, you correctly thought that if you take too many coins, the twin will suspect the deception. So, you've decided to stick to the following strategy to avoid suspicions: you take the minimum number of coins, whose sum of values is strictly more than the sum of values of the remaining coins. On this basis, determine what minimum number of coins you need to take to divide them in the described manner.
Input
The first line contains integer n (1 ≤ n ≤ 100) — the number of coins. The second line contains a sequence of n integers a1, a2, ..., an (1 ≤ ai ≤ 100) — the coins' values. All numbers are separated with spaces.
Output
In the single line print the single number — the minimum needed number of coins.
Examples
Input
2
3 3
Output
2
Input
3
2 1 2
Output
2
Note
In the first sample you will have to take 2 coins (you and your twin have sums equal to 6, 0 correspondingly). If you take 1 coin, you get sums 3, 3. If you take 0 coins, you get sums 0, 6. Those variants do not satisfy you as your sum should be strictly more that your twins' sum.
In the second sample one coin isn't enough for us, too. You can pick coins with values 1, 2 or 2, 2. In any case, the minimum number of coins equals 2.
解题思路:题目的意思就是有n块硬币,要求从中挑选出num个硬币,使得其价值总和nowsum刚好大于剩下硬币的价值总和sum,并且num是最小。怎么解决呢?将币值排序(从小到大),然后从后(币值较大的硬币)往前依次取硬币,只要第一次出现nowsum>sum,此时的num就是要取的最小硬币数,小贪心,水过。
AC代码:
#include<bits/stdc++.h>
using namespace std;
int main(){
int n,a[],sum=,num=,nowsum=;
cin>>n;
for(int i=;i<n;++i){cin>>a[i];sum+=a[i];}
sort(a,a+n);
for(int i=n-;i>=;--i){
nowsum+=a[i];sum-=a[i];num++;
if(nowsum>sum)break;
}
cout<<num<<endl;
return ;
}
C - Twins(贪心)的更多相关文章
- Codeforce 140C (贪心+优先队列)补题
C. New Year Snowmen time limit per test2 seconds memory limit per test256 megabytes inputstandard in ...
- BZOJ 1692: [Usaco2007 Dec]队列变换 [后缀数组 贪心]
1692: [Usaco2007 Dec]队列变换 Time Limit: 5 Sec Memory Limit: 64 MBSubmit: 1383 Solved: 582[Submit][St ...
- HDOJ 1051. Wooden Sticks 贪心 结构体排序
Wooden Sticks Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others) To ...
- HDOJ 1009. Fat Mouse' Trade 贪心 结构体排序
FatMouse' Trade Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others) ...
- BZOJ 1691: [Usaco2007 Dec]挑剔的美食家 [treap 贪心]
1691: [Usaco2007 Dec]挑剔的美食家 Time Limit: 5 Sec Memory Limit: 64 MBSubmit: 786 Solved: 391[Submit][S ...
- 【Codeforces 738D】Sea Battle(贪心)
http://codeforces.com/contest/738/problem/D Galya is playing one-dimensional Sea Battle on a 1 × n g ...
- 【BZOJ-4245】OR-XOR 按位贪心
4245: [ONTAK2015]OR-XOR Time Limit: 10 Sec Memory Limit: 256 MBSubmit: 486 Solved: 266[Submit][Sta ...
- code vs 1098 均分纸牌(贪心)
1098 均分纸牌 2002年NOIP全国联赛提高组 时间限制: 1 s 空间限制: 128000 KB 题目等级 : 黄金 Gold 题解 题目描述 Description 有 N 堆纸牌 ...
- 【BZOJ1623】 [Usaco2008 Open]Cow Cars 奶牛飞车 贪心
SB贪心,一开始还想着用二分,看了眼黄学长的blog,发现自己SB了... 最小道路=已选取的奶牛/道路总数. #include <iostream> #include <cstdi ...
随机推荐
- ROS和OpenCV的对接cv_bridge
做一个诚实的ROS教程搬运工............................. 官网链接:http://wiki.ros.org/cv_bridge 一.Package Summary Rel ...
- Vue2 封装的 Quill 富文本编辑器组件 Vue-Quill-Editor
1.安装 npm install vue-quill-editor --save 2.使用 import { quillEditor } from 'vue-quill-editor' 3.组件中 & ...
- Bamboo Django Celery定时任务和时间设置
1.Celery加入定时任务 Celery除了可以异步执行任务之外,还可以定时执行任务.在实例代码的基础上写个测试方法: 1 #coding:utf-8 2 from celery.task.sche ...
- 32.es读请示内部分发原理
当客户端发送一次读请求时,大致会经过以下几个步骤 1.客户端发送一个请求过去,es的一个node接收到这个请求(随机的node),这个node就被es内部分配成coordinating node(协调 ...
- 1069. The Black Hole of Numbers
For any 4-digit integer except the ones with all the digits being the same, if we sort the digits in ...
- 搜索引擎seo优化
<a href="" title="SEO优化"></a> <img src="" alt="SEO ...
- EurekaLog是什么鬼?
D的all工程文件打开后,莫名其妙就处于等待打开状态.因为最后一次调整是安装了RO9.0.所以一直怀疑是RO的原因.再加上win7授权问题,安装RO一直不顺当.所以折腾的时间最多. 其他把RO全部卸载 ...
- 【[Offer收割]编程练习赛11 C】岛屿3
[题目链接]:http://hihocoder.com/problemset/problem/1487 [题意] 中文题 [题解] 岛屿的数目对应了这个图中联通块的数目; 面积则对应有多少个方块; 周 ...
- firefox历史版本下载地址
http://ftp.mozilla.org/pub/firefox/releases/
- 译:滑雪租赁问题(ski rental problem)
本文翻译自维基百科词条:http://en.wikipedia.org/wiki/Ski_rental_problem 滑雪租赁问题(ski rental problem)是一类问题的总称, ...