#include<bits/stdc++.h>
using namespace std;

#define rep(i,n) for(int i=0;i<(n);i++)
#define REP(i,a,b) for(int i=(a);i<(b);i++)
#define pb push_back
#define all(v) (v).begin(),(v).end()
typedef vector<int>vi;
int main(){
    int x,y,z;cin>>x>>y>>z;
    vi a,b;
    a.pb(x+y);a.pb(y+z);a.pb(z+x);
    rep(i,3){
        int l;cin>>l;b.pb(l);
    }
    
    sort(all(a));
    sort(all(b));reverse(all(b));
    
    int val=0;
    rep(i,3)val+=a[i]*b[i]*2;
    cout<<val<<endl;

    return 0;
}