Simplifying chips

Posted by Koen_Be3840 on
URL: http://nand2tetris-questions-and-answers-forum.52.s1.nabble.com/Simplifying-chips-tp4025264.html

In discussions Xor is always represented with these parts
    Not(in=a, out=nota); (1 Nand)
    Not(in=b, out=notb); (1 Nand)
    And(a=a, b=notb, out=w1); (2 Nand)
    And(a=nota, b=b, out=w2); (2 Nand)
    Or(a=w1, b=w2, out=out); (3 Nand)

I found

    Nand(a=a,b=b,out=naab);
    Nand(a=a,b=naab,out=w1);
    Nand(a=naab,b=b,out=w2);
    Nand(a=w1,b=w2,out=out);

4 against 9

As i went on with the course

Mux 4 against 8
HalfAdder 5 against 6 (with Xor 4 Nand) else 5 against 11
FullAdder 9 against 13 (with my halfadder) else 9 against 15 or even 9 against 25 (Xor)

At what point do i stop simplifying these chips?