#!/usr/bin/perl

   use Benchmark;

   $fact = $ARGV[0] || 10;

   timethese(16000, {'recurse'=>'recurse($fact)',
                     'nocurse'=>'nocurse($fact)'});

sub recurse {
   my ($n) = @_;
   if ($n == 0) { return 1; }
   return ($n * recurse($n-1));
}

sub nocurse {
   my ($n) = @_;
   my $f = 1;
   for my $i (1..$n) { $f *= $i; }
   return $f;
}