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