2117: Pseudoprime numbers
内存限制:128 MB
时间限制:1.000 S
评测方式:文本比较
命题人:
提交:39
解决:19
题目描述
Fermat's theorem states that for any prime number p and for any integer a > 1, ap = a (mod p). That is, if we raise a to the pth power and divide by p, the remainder is a. Some (but not very many) non-prime values of p, known as base-a pseudoprimes, have this property for some a. (And some, known as Carmichael Numbers, are base-a pseudoprimes for all a.)
Given 2 < p ≤ 1000000000 and 1 < a < p, determine whether or not p is a base-a pseudoprime.
输入
Input contains several test cases followed by a line containing "0 0". Each test case consists of a line containing p and a.
输出
For each test case, output "yes" if p is a base-a pseudoprime; otherwise output "no".
样例输入 复制
3 2
10 3
341 2
341 3
0 0
样例输出 复制
no
no
yes
no