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PROOT - Primitive Root |
In the field of Cryptography, prime numbers play an important role. We are interested in a scheme called "Diffie-Hellman" key exchange which allows two communicating parties to exchange a secret key. This method requires a prime number p and r which is a primitive root of p to be publicly known. For a prime number p, r is a primitive root if and only if it's exponents r, r2, r3 ... rp-1 are distinct (mod p).
Cryptography Experts Group (CEG) is trying to develop such a system. They want to have a list of prime numbers and their primitive roots. You are going to write a program to help them. Given a prime number p and another integer r < p, you need to tell whether r is a primitive root of p.
Input
There will be multiple test cases. Each test case starts with two integers p (p < 231) and n (1 ≤ n ≤ 100) separated by a space on a single line. p is the prime number we want to use and n is the number of candidates we need to check. Then n lines follow each containing a single integer to check. An empty line follows each test case and the end of test cases is indicated by p=0 and n=0 and it should not be processed. The number of test cases is at most 60.
Output
For each test case print "YES" (quotes for clarity) if r is a primitive root of p and "NO" (again quotes for clarity) otherwise.
Example
Input: 5 2 3 4 7 2 3 4 0 0 Output: YES NO YES NO
Explanation
In the first test case 31, 32 , 33 and 34 are respectively 3, 4, 2 and 1 (mod 5). So, 3 is a primitive root of 5.
41, 42 , 43 and 44 are respectively 4, 1, 4 and 1 respectively. So, 4 is not a primitive root of 5.
Added by: | Swarnaprakash |
Date: | 2009-01-14 |
Time limit: | 1s |
Source limit: | 50000B |
Memory limit: | 1536MB |
Cluster: | Cube (Intel G860) |
Languages: | C C++ 4.3.2 CPP JAVA |
Resource: | Kurukshetra 09 OPC |
Public source code since: | 2013-04-04 06:00:00 |