#include <fstream>
using namespace std;

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

void euclid(int a, int b, int* d, int* x, int* y);

int main()
{
	int a, n;
	
	fin >> a >> n;
	
	int x, y, d;
	
	euclid(a, n, &d, &x, &y);
	
	if (x < 0)
	{
		x = (n + x) % n;
	}
	
	fout << x;
	
	fin.close();
	fout.close();
	return 0;
}

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