#include <iostream>
#include <fstream>

using namespace std;

#define cin fin
#define cout fout

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

void euclid(long long a, long long b, long long& x, long long& y);

int main()
{
    long long a, n, x, y;

    cin >> a >> n;

    euclid(a, n, x, y);

    cout << x % n;

    return 0;
}

void euclid(long long a, long long b, long long& x, long long& y)
{
    if(b == 0)
    {
        y = 0;
        x = 1;
    }
    else
    {
        long long x1, y1;

        euclid(b, a % b, x1, y1);

        x = y1;
        y = x1 - a / b * y1;
    }
}