#include <cstdlib>
#include <fstream>

using namespace std;

inline void gcd(int a, int b, int& x, int& y)
{
    if(!b)
    {
        x = 1;
        y = 0;
    }
    else {
            int x0, y0;

            gcd(b, a % b, x0, y0);

            x = y0;
            y = x0 - (a / b) * y0;
         }
}

int main()
{
    int A, N, x, y;
    ifstream in("inversmodular.in");
    ofstream out("inversmodular.out");

    in >> A >> N;
    gcd(A, N, x, y);
    if(x < 0) x += N;
    out << x << '\n';

    return EXIT_SUCCESS;
}