#include<fstream>
#define FILE ifstream cin("mod.in");ofstream cout("mod.out");
using namespace std;
FILE
inline int gcd(int x,int y)
{
	return x==0?y:gcd(y%x,x);
}
inline void ex_gcd(int a,int b,int& x,int& y)
{
	if(b==0)
	{
		x=1;
		y=0;
		return ;
	}
	ex_gcd(b,a%b,y,x);
	y-=a/b*x;
}
int a,b,t,x,y;
int lyh()
{
	cin>>a>>b;
	t=gcd(a,b);
	a/=t;
	b/=t;
	ex_gcd(a,b,x,y);
	while(x<0)
		x+=b;
	cout<<x<<endl;
	cin.close();
	cout.close();
	return 0;
}
int Main=lyh();
int main(){;}