#include <iostream>
#include <fstream>
using namespace std;
void euclid_extins(long long a, long long b, long long *d, long long *x, long long *y)
{
	if (b == 0)
	{
		*d = a;
		*x = 1;
		*y = 0;
	}
	else
	{
		long long x0, y0;
		euclid_extins(b, a % b, d, &x0, &y0);
		*x = y0;
		*y = x0 - (a / b) * y0;
	}
}
int main ()
{
	long long A,N,d,x,y;
	ifstream fi("inversmodular.in");
	ofstream fo("inversmodular.out");
	fi>>A>>N;
	euclid_extins(A,N,&d,&x,&y);
	while(x<0) x += N;
	fo << x << "\n";
	return 0;
}