>>7
>>8
Yeah, I failed it. b=1, c=0, d=1 fails it, too. Either way, I don't quite see the advantage of that "simplification." Is two XORs and an AND that much quicker than two ANDs, an OR, and a NOT? Especially when you get the advantage of short circuiting with the or? (b=1, c=1 means d doesn't ever have to get evaluated). The "simplification" seems much more complicated to read, and slower to boot.