#include <fstream>

using namespace std;

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

void cmmdc(int a, int b, int &x, int &y)
{
    if(!b)
    {
        x = 1, y = 0;
        return;
    }

    int q = a / b, x1, y1;
    cmmdc(b, a % b, x1, y1);
    x = y1;
    y = x1 - q * y1;
}

int A, N;

int main()
{
    in >> A >> N;
    int x, y;
    cmmdc(A, N, x, y);
    while(x < 0)
        x += N;
    out << x << '\n';
    return 0;
}