#include<fstream>
using namespace std;

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

void euclid_ext(int a, int b, int &x, int &y)
{
	if (b != 0)
	{
		int x0, y0;
		euclid_ext(b, a%b, x0, y0);

		x = y0;
		y = x0 - y0*(a / b);

	}
	else
	{
		x = 1, y = 0;
	}
}

int main()
{
	int a, N;

	in >> a >> N;

	int x, y;

	euclid_ext(a, N, x, y);

	while (x < 0)
		x += N;

	out << x;



	return 0;
}