import java.util.Arrays;
import java.util.Scanner;


public class Main_yukicoder268 {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        int[] l = new int[3];
        int[] ll = new int[3];
        int[] c = new int[3];
        for (int i = 0; i < 3; i++) {
        	l[i] = sc.nextInt();
        }
        ll[0] = l[0] + l[1];
        ll[1] = l[1] + l[2];
        ll[2] = l[0] + l[2];
        for (int i = 0; i < 3; i++) {
        	c[i] = sc.nextInt();
        }
        Arrays.sort(ll);
        Arrays.sort(c);

        int ret = 0;
        for (int i = 0; i < 3; i++) {
        	ret += 2 * ll[i] * c[2 - i];
        }

        System.out.println(ret);

        sc.close();
    }
}