using System;using System.Linq;class A{static void Main(){
char[]c={' ','\n'};
int[]a=Console.In.ReadToEnd().Split(c).Take(12).Select(Int32.Parse).ToArray();
int s=0,p=0,q=0;
for(int z=9;z-->0;a[z%9]-=a[9+z%3],s+=a[z%3]*=a[p=3+(z+1)%3]*a[q=6+(z+2)%3]-a[q-3]*a[p+3]);
Console.Write(s/6);
}}