#include <iostream>
#include <algorithm>
using namespace std;

int main(){
   int l[3],p[3];
   cin >> l[0] >> l[1] >> l[2] >> p[0] >> p[1] >> p[2];
   stable_sort(l,l + 3);
   stable_sort(p,p + 3);
   cout << 2 * p[2] * (l[0] + l[1]) + 2 * p[1] * (l[0] + l[2]) + 2 * p[0] * (l[1] + l[2]) << endl;
}