import java.util.*;interface A{static void main(String[]a){int i=0,x=0,X[]=new int[12];for(Scanner s=new Scanner(System.in);i<12;)x+=i/9*(X[i]=s.nextInt()-X[i%3])*(X[++i%3+3]*X[-~i%3+6]-X[i%3+6]*X[3-~i%3]);System.out.print(x/6);}}