1., 2. see perlman strict, chapter 'strict vars'
as in a previuos thread already mentioned :-)
$a and $b arre exempted from the strict vars pragma due to their special role in the sort function
3. undef equals to '0'
4. dunno, didn't read it yet :-)

Have a nice day
All decision is left to your taste

In reply to Re: •Perl Puzzle, was Re: (OT?) n(n-1)/2 by little
in thread (OT?) n(n-1)/2 by mandog

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