It's normally best to end recursive solutions with the recursive call. That allows the compiler to use tail-recursion to speed up the solution.

Of course, in Perl you need to jump through a few hoops to do use tail-recursion, so I mentioned but didn't include it in my original node. But with a bit if tinkering you can use it, and here it is now: 

sub max {
    my $max  = shift;
    my $next = shift;
    return $max if not $next;
    unshift @_, $max > $next ? $max : $next;
    goto &max;
}

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Which I estimate to be about 10x faster on a random 5000 element list. (Exact benchmarks are left to the reader as an exercise :-).

I wonder if Ponie (Perl 5 On New Internals Engine) will be able to detect and use tail-recursion.

elusion : http://matt.diephouse.com

In reply to Re^3: Finding the max()/min() by elusion
in thread Finding the max()/min() by dragonchild

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