#include <bits/stdc++.h>
#define ll long long
#define ull unsigned long long int
#define ii pair<int,int>
#define lli pair<ll,ll>
#define pii pair<int,int>
#include<limits>
#define deb(x) cout<<#x<<'='<<(x)<<endl
#define deb2(x,y) cout<<'['<<#x<<'='<<(x)<<','<<#y<<'='<<(y)<<']'<<endl
#define debarr(a,n) {cout<<#a<<'='; for(int i=0;i<n;i++) cout << a[i] << ' '; cout<<endl;}
#define debvec(v) {cout<<#v<<'=';for(auto itr=v.begin();itr!=v.end();itr++)cout<<*itr<<' ';cout<<endl;}
#define INF numeric_limits<int>::max()
#define NINF numeric_limits<int>::min()
#define endl "\n"
#define MP make_pair
#define SZ(x) ((int)(x).size())
#define MOD (pow(10,9)+7)
using namespace std;

ll mod(ll n,ll a)
{
    string num = to_string(n);
    ll res= 0;
    for(auto i=0;i<num.length();i++)
    {
        res=(res*10+(ll)num[i]-'0')%a;
    }
    return res;
}




int main()
{
    ios_base::sync_with_stdio(false); 
    cin.tie(nullptr);
    cout.tie(nullptr);
    // ll tc;
    // cin>>tc;
    // while(tc--)
    {
          ll a,b;
        cin>>a>>b;
        // a = sqrt(a);
        // b= sqrt(b);
        if(a==b) cout<<4<<endl;
        else if(b==2*a )cout<<4<<endl;
        else if(b>a && b<2*a) cout<<8<<endl;
        else cout<<0<<endl;

    }
    return 0;
}