#include <fstream.h>

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

int main ()
{
	long a, b, x, y, d;
	ifstream fin ("inversmodular.in");
	ofstream fout ("inversmodular.out");
	fin >> a >> b;
	d = euclid (a, b, x, y);
	x *= (1 / d);
	while (x <= 0)
	{
		x += b;
	}
	fout << x;
	fin.close ();
	fout.close ();
	return 0;
}