| Time Limit: 1000MS | Memory Limit: 65536K | |
| Total Submissions: 6033 | Accepted: 3351 |
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 老师给糖给 1 2号学生,然后接下来隔着一个学生给糖,隔着两个学生给糖,问一直这样下去,是否所有学生都会拿到糖? 找规律，判断 n是否为 2^k...快速判断 n是否为 2的指数幂的方法 n&n-1...
#include <stdio.h>
#include <algorithm>
#include <string.h>
using namespace std;
typedef long long LL;
const int N = ; int main()
{
int n;
while(scanf("%d",&n)!=EOF){
if((n&(n-))==) printf("YES\n");
else printf("NO\n");
}
return ;
}