#include <bits/stdc++.h>
#define p(s) cout<<(s)<<endl
using namespace std;
int main(){
	int L[3];
	int C[3];
	cin>>L[0]>>L[1]>>L[2];
	cin>>C[0]>>C[1]>>C[2];
	sort(L,L+3);
	sort(C,C+3);
	p(((L[0]+L[1])*C[2]+(L[0]+L[2])*C[1]+(L[1]+L[2])*C[0])*2);
	return 0;
}