#include<iostream>
using namespace std;

inline void gcd(int a, int b, int& x, int& y)
{
	if (b == 0)
	{
		x = 1;
		y = 0;
	}
	else
	{
		int x0, y0;
		gcd(b, a % b, x0, y0);
		x = y0;
		y = x0 - (a / b) * y0;
	}
}
int main()
{
	freopen("inversmodular.in", "r", stdin);
	freopen("inversmodular.out", "r", stdout);
	int a, n;
	cin >> a >> n;
	int x, y;
	gcd(a, n, x, y);
	while (x < 0)
		x += n;
	cout << x;
}