#include <iostream>
#include <fstream>

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;
        return;
    }
    int x0, y0;
    euclid(b, a % b, x0, y0);
    x = y0;
    y = x0 - (a / b) * y0;
}

int main()
{
    fin >> a >> n;

    int x, y;
    euclid(a, n, x, y);

    fout << (x >= 0 ? x : (x + n) % n);

    fin.close();
    fout.close();
    return 0;
}