#include <fstream>

using namespace std;

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

int a, n, X, Y;

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

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

int main()
{
	cin >> a >> n;
	euclid(a, n, X, Y);
	if (X < 0)
		X += n;

	cout << X;
	return 0;
}