Sunday, October 22, 2017

11287 - Pseudoprime Numbers

/***

            Bismillahir Rahmanir Rahim
            Read the name of Allah, who created you!!!
            Author : Shah Newaj Rabbi Shishir
            Department of CSE, City University, Bangladesh.

***/

#include <bits/stdc++.h>
using namespace std;

#define sf scanf
#define pf printf
#define fast ios_base::sync_with_stdio(0),cin.tie(0),cout.tie(0)
#define scase sf ("%d",&tc)
#define sn sf ("%d",&n)
#define whilecase while (tc--)
#define eof while (cin >> n)
#define forloop for (pos=1; pos<=tc; pos++)
#define arrayloop (i=0; i<n; i++)
#define cinstr cin >> str
#define getstr getline (cin,str)
#define pcase pf ("Case %d: ",pos)
#define pii pair <int,int>
#define pb push_back
#define in insert
#define llu unsigned long long
#define lld long long
#define U unsigned int
#define endl "\n"

const int MOD = 1000000007;
const int MAX = 1000005;

U bigmod (U b,U p,U m)
{
    llu p1,p2;

    if (p == 0)
        return 1;

    if (p & 1)
    {
        p1 = b % m;
        p2 = bigmod (b,p-1,m) % m;
        return (p1 * p2) % m;
    }
    else
    {
        p1 = bigmod (b,p/2,m) % m;
        return (p1 * p1) % m;
    }
}

bool isPrime (U n)
{
    if (n < 2 || (!(n & 1) && n != 2))
        return false;

    if (n == 2)
        return true;

    for (U i=2; i*i<=n; i++)
        if (n % i == 0)
            return false;

    return true;
}

int main (void)
{
    /*
    freopen ("input.txt","r",stdin);
    freopen ("output.txt","w",stdout);
    */

    U a,p;

    while (sf ("%u %u",&p,&a) && p && a)
    {
        if (!isPrime(p) && bigmod(a,p,p) == a)
            pf ("yes\n");
        else
            pf ("no\n");
    }

    return 0;
}

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