#include <iostream>
#include <fstream>
using namespace std;

ifstream fin("inversmodular.in");
ofstream fout("inversmodular.out");

long long A, N;

void gcd(long long &x, long long &y, int a, int b)
{
    if(b == 0){
        x = 1;
        y = 0;
    }
    else
    {
        gcd(x,y,b,a%b);
        long long aux = x;
        x = y;
        y = aux - y * (a / b);
    }
}

int main()
{
    long long inv, ins;
    fin >> A >> N;
    gcd(inv,ins,A,N);
    if(inv <= 0){
        inv = N + inv % N;
    }
    fout << inv << "\n";
    return 0;
}