[erlang-questions] Erlang again!
Fri Jul 23 01:51:20 CEST 2010
On Jul 23, 2010, at 3:52 AM, Corrado Santoro wrote:
> Try this:
> sub (,) -> ;
> sub (_, ) -> ;
> sub (, _) -> ;
> sub ([H1 | T1], [H2 | T2]) -> [ H2 - H1 | sub (T1, T2)].
Don't. Why write three clauses when one will do?
sub([X|Xs], [Y|Ys]) -> [X-Y | sub(Xs, Ys)];
sub(_, _ ) -> .
Then think about whether you really want sub(boojum, ) to answer
, or whether you really want sub([2,3], [1|missing]) to return
, and make the second clause
sub(, ) -> .
> not tail-recursive... however :-)
Tail recursion is important, but body recursion is not the
Dark Side of the Source.
"FIRST make it right,
THEN (try to) make it fast(er)."
More information about the erlang-questions