poj3372

最新推荐文章于 2019-08-30 10:53:38 发布

weixin_34178244

最新推荐文章于 2019-08-30 10:53:38 发布

阅读量57

点赞数

CC 4.0 BY-SA版权

原文链接：http://www.cnblogs.com/shenben/p/5578786.html

本文探讨了一个有趣的问题：老师如何在一圈孩子中分配糖果，并确保每位孩子至少获得一颗糖果。通过数学分析，得出结论：只有当孩子数量为2的幂次方时，所有孩子才能得到糖果。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

Candy Distribution

Time Limit: 1000MS		Memory Limit: 65536K
Total Submissions: 5868		Accepted: 3274

Description

N children standing in circle who are numbered 1 through N clockwise are waiting their candies. Their teacher distributes the candies by in the following way:

First the teacher gives child No.1 and No.2 a candy each. Then he walks clockwise along the circle, skipping one child (child No.3) and giving the next one (child No.4) a candy. And then he goes on his walk, skipping two children (child No.5 and No.6) and giving the next one (child No.7) a candy. And so on.

Now you have to tell the teacher whether all the children will get at least one candy?

Input

The input consists of several data sets, each containing a positive integer N (2 ≤ N ≤ 1,000,000,000).

Output

For each data set the output should be either "YES" or "NO".

Sample Input

2
3 
4

Sample Output

YES
NO
YES

Source

POJ Monthly--2007.09.09, ailyanlu@zsu

这是一个复杂的数学问题，但是可以通过小数据猜测出来，最后发现只要是2的幂就行，否则不行

#include<cstdio>
using namespace std;
int main()
{
    int n;
    while(scanf("%d",&n)==1)
    {
        while(n%2==0)
            n/= 2;
        if(n==1)
            printf("YES\n");
        else
            printf("NO\n");
    }
    return 0;
}