#include <iostream>
#include <fstream>

using namespace std;

void gcd_extended(int a, int b, int &x, int &y)
{
    if (!b)
    {
        x = 1;
        y = 0;
        return;
    }
    gcd_extended(b, a%b, x, y);
    int aux = x;
    x = y;
    y = aux - (a / b) * x;
}

int main()
{
    ifstream fin("inversmodular.in");
    ofstream fout("inversmodular.out");
    int a, n, x, y;
    fin >> a >> n;
    gcd_extended(a, n, x, y);
    if (x < 0)
        x += n;
    fout << x;
    return 0;
}