#include <iostream>
#include <fstream>

using namespace std;

ifstream f("inversmodular.in");
ofstream g("inversmodular.out");

int gcd(int a, int b, int &x, int &y){
    if(b == 0){
        x = 1;
        y = 0;
        return a;
    }
    int d,xp,yp;
    d = gcd(b, a % b, xp, yp);
    x = yp;
    y = xp - yp * (a / b);
    return d;
}

int main()
{
    int a,n;
    f >> a >> n;
    int inv = 0,y,d;
    d = gcd(a,n,inv,y);
    if(inv <= 0){
        inv = n + inv % n;
    }
    g << inv;
    return 0;
}