#include <fstream>
using namespace std;

ifstream fin("inversmodular.in");
ofstream fout("inversmodular.out");
int A, N;

void gcd(long long &x, long long &y, int a, int b)
{
    if (!b)
        x = 1, y = 0;
    else
    {
        gcd(x, y, b, a % b);
        long long aux = x;
        x = y;
        y = aux - y * (a / b);
    }
}

int main()
{
    ios::sync_with_stdio(false);
    long long inv = 0, ins;
    fin>>A>>N;
    fin.close();
    gcd(inv, ins, A, N);
    if (inv <= 0)
        inv = N + inv % N;
    fout<<inv;
    fout.close();
    return 0;
}