#include <bits/stdc++.h>

using namespace std;

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

int A, 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;
    }
}

void Rezolvare()
{
    fin >> A >> N;
    int x, y;
    Euclid(A, N, x, y);
    while (x < 0)
        x += N;
    fout << x << '\n';
}

int main()
{
    Rezolvare();
    fin.close();
    fout.close();
    return 0;
}