# Pseudoprime numbers

Time Limit: 1000MS

Memory Limit: 65536K

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## Description

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.

## Input

Input contains several test cases followed by a line containing "0 0". Each test case consists of a line containing p and a.

## Output

For each test case, output "yes" if p is a base-a pseudoprime; otherwise output "no".

## Sample Input

3 2
10 3
341 2
341 3
1105 2
1105 3
0 0


## Sample Output

no
no
yes
no
yes
yes


## Source

Waterloo Local Contest, 2007.9.23