【HDU1222】 Wolf and Rabbit(GCD)-优快云博客

本文介绍了一个简单的数学问题，通过计算两个正整数的最大公约数（GCD），判断狼能否找到藏在洞里的兔子。如果最大公约数为1，则狼可以遍历所有洞找到兔子；否则存在安全洞让兔子生存。

 There is a hill with n holes around. The holes are signed from 0 to n-1.

这里写链接内容

A rabbit must hide in one of the holes. A wolf searches the rabbit in anticlockwise order. The first hole he get into is the one signed with 0. Then he will get into the hole every m holes. For example, m=2 and n=6, the wolf will get into the holes which are signed 0,2,4,0. If the rabbit hides in the hole which signed 1,3 or 5, she will survive. So we call these holes the safe holes.

Input
The input starts with a positive integer P which indicates the number of test cases. Then on the following P lines,each line consists 2 positive integer m and n(0 < m,n<2147483648).
Output
For each input m n, if safe holes exist, you should output “YES”, else output “NO” in a single line.
Sample Input

2
1 2
2 2

Sample Output

NO

很简单的一道运用gcd的题目，直接应用就好啦

#include<stdio.h>
int gcd(int a,int b)
{
    return !b?a:gcd(b,a%b);
}
int main()
{
    long long m,n,t;
    scanf("%d",&t);
    while(t--)
    {
        scanf("%lld%lld",&m,&n);
        printf("%s\n",gcd(m,n)==1?"NO":"YES");
    }
return 0;
}