import java.io.*;
import java.util.*;

class Main {
	
	public static void out (Object o) {
		System.out.println(o);
	}
	
	public static void main (String[] args) throws IOException {
		BufferedReader br = 
			new BufferedReader(new InputStreamReader(System.in));
		
		int size = 3;
		String[] line1 = br.readLine().split(" ");
		int[] a = new int[size];
		for (int i = 0; i < size; i++) a[i] = Integer.parseInt(line1[i]);
		
		String[] line2 = br.readLine().split(" ");
		int[] b = new int[size];
		for (int i = 0; i < size; i++) b[i] = Integer.parseInt(line2[i]);
		int[] c = new int[]{b[0] + b[1] , b[1] + b[2] , b[2] + b[0]};
		
		Arrays.sort(a);
		Arrays.sort(c);
		
		out(2 * (a[0] * c[2] + a[1] * c[1] + a[2] * c[0]));
	}
}