#include <fstream>

using namespace std;

ifstream cin("inversmodular.in");
ofstream cout("inversmodular.out");

int gcd(int a, int b, int &x, int &y)
{
    if (b == 0)
    {
        x = 1;
        y = 0;
        return a;
    }
    else
    {
        int x0, y0, d;
        d = gcd(b, a % b, x0, y0);
        x = y0;
        y = x0 - (a / b) * y0;
        return d;
    }
}

int main()
{
    int a, n, x, y;
    cin >> a >> n;
    int d = gcd(a, n, x, y);
    while (x < 0)
    {
        x += n;
    }
    cout << x;
    return 0;
}