#include<iostream>
using namespace std;
long gcd(long a,long b){return b?gcd(b,a%b):a;}
long P,Q;
int main()
{
	cin>>P>>Q;
	long Lp=0,Lq=1,Rp=1,Rq=0;
	for(int q=1;q<Q;q++)
	{
		{//L
			long p=(q*P+Q-1)/Q-1;
			while(p>0&&gcd(p,q)>1)p--;
			if(Lp*q<p*Lq)Lp=p,Lq=q;
		}
		{//R
			long p=P*q/Q+1;
			while(gcd(p,q)>1)p++;
			if(Rp*q>p*Rq)Rp=p,Rq=q;
		}
	}
	cout<<Lp+Lq+Rp+Rq<<endl;
}