#include <iostream>
#include <fstream>

using namespace std;

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

int c, n;

void Euclid(int a, int b, int &x, int &y)
{
    if(!b)
    {
        x = 1;
        y = 0;
    }
    else
    {
        int x0, y0;
        Euclid(b, a%b, x0, y0);
        x = y0;
        y = x0 - (a / b) * y0;
    }
}

int main()
{
    int x = 0, y;
    fin>>c>>n;
    Euclid(c, n, x, y);
    if(x <= 0)
        x = n + x % n;
    fout<<x;
    return 0;
}