2 Mar
2023
2 Mar
'23
8:12 a.m.
On Mar 1, 2023, at 5:36 PM, Noel Chiappa <jnc(a)mercury.lcs.mit.edu> wrote:
Steve Ward told another oral story which I'm pretty sure _is_ true, though.
They ask the candidate to design a state machine (or digital logic, I forget
which) which can tell if a number is divisible by three (I think I have the
details correct, but I'm not absolutely certain). So they describe one - and
then point out that you can feed the number in from either end (most or least
significant end first) - and proves that it will work either way! The
committee was blown away.
Doesn't everyone know that a number is divisible by 3 if the one digit
result after casting out 9s is divisible by 3?