#include <iostream>
#include <fstream>

using namespace std;

ifstream fin("euclid3.in");
ofstream fout("euclid3.out");

void euclid2(int a, int b, int *d, int *x, int *y)
{
    if (b == 0)
    {
        *d = a;
        *x = 1;
        *y = 0;
    }
    else
    {
        int x0, y0;
        euclid2(b, a % b, d, &x0, &y0);
        *x = y0;
        *y = x0 - (a / b) * y0;
    }
}

int invers_modular(int a, int n)
{
    int x, y, d;
    euclid2(n, a, &d, &x, &y);
    while (y < 0)
        y += n;
    return y;
}

int main()
{
    int a, n;
    fin >> a >> n;
    fout << invers_modular(a, n);
    return 0;
}