If you're just doing this for Perl education, don't bother with useless mathematical optimizations. In real life, you can often sacrifice a bit of speed for ease of coding. 

my $a = 0;
$a += $_ for 1..1000;
print "Answer: $a\n";

[download]

If this isn't about Perl programming, or about programming at all, you're posting in the wrong place :)

P.S. With Perl Golf, of course mathematic principles are a lot more important: $foo && ($foo % 9 || 9) is shorter than substr($foo, 0, 1) + substr($foo, 1, 1) (and do it again if the answer's >9) 

++ vs lbh qrpbqrq guvf hfvat n ge va Crey :)
Nabgure bar vs lbh qvq fb jvgubhg ernqvat n znahny svefg.
-- vs lbh hfrq OFQ pnrfne ;)
    - Whreq

In reply to Re: (OT?) n(n-1)/2 by Juerd
in thread (OT?) n(n-1)/2 by mandog

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