#include <iostream>
#include <fstream>

using namespace std;
ifstream in("inversmodular.in");
ofstream out("inversmodular.out");

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

int main()
{
    long long int A, N, x, y;
    in >> A >> N;
    long long int gcd;
    euclid(A, N, &gcd, &x, &y);
    long long int  inverse = (x % N + N) % N;
    if (inverse <= 0)
        inverse = N + inverse % N;
    out << inverse;
    return 0;
}