#include<bits/stdc++.h>
using namespace std;
long long tmp,m,mun;
void find(long long x,long long y)
{
	if(x==y)
	{
		mun+=x*4;
		return;
	}
	tmp=min(x,y);
	if(x>y)
		x-=tmp;
	else if(y>x)
		y-=tmp;
	mun+=tmp*4;
	find(x,y);
}
int main()
{
	long long x,y;
	cin>>x>>y;
	if(x==y){
		cout<<x*4;
		return 0;
	}
	find(x,y);
	cout<<mun;
	return 0;
 }