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Postings from April 2002
On Monday, April 29, 2002, at 02:34 , Nikola Janceski wrote:
> what about?
>
> my @numbers = 1..100;
> while($#numbers >= 0) {
> my $index = rand $numofques;
> my $element = $numbers[$index];
> $numbers[$index] = pop @numbers; # replace the number we used with
> the
> last element and shrink array
> printf "%-3d ", $element;
> }
> printf "\n"
>
> Wouldn't this run faster?
i found a few defects in it, and replaced them
sub nikolaPopper {
my @retarray =();
my @numbers = @array;
while($#numbers >= 0) {
my $index = rand $#numbers;
push(@retarray, $numbers[$index]);
# otherwise we never close the while loop....
if ($#numbers > 0 ) {
$numbers[$index] = pop @numbers; # replace the number we used with
the
# last element and shrink array
} else {
my $junk = pop @numbers;
}
}
@retarray;
} # end of nikolaPopper
the ballscores look like:
perl ran*
running with array size 2500
Benchmark: timing 500 iterations of consume, decLoop, nikolaPopper,
seenArray...
consume: 14 wallclock secs (14.32 usr + 0.00 sys = 14.32 CPU) @ 34.92/
s (n=500)
decLoop: 16 wallclock secs (14.55 usr + 0.00 sys = 14.55 CPU) @ 34.36/
s (n=500)
nikolaPopper: 17 wallclock secs (17.40 usr + 0.00 sys = 17.40 CPU) @
28.74/s (n=500)
^C
[jeeves:~/perl/benchmark] drieux% !!
perl ran*
running with array size 250000
Benchmark: timing 50 iterations of consume, decLoop, nikolaPopper,
seenArray...
consume: 3196 wallclock secs (3149.69 usr + 0.00 sys = 3149.69 CPU) @
0.02/s (n=50)
decLoop: 180 wallclock secs (179.24 usr + 0.00 sys = 179.24 CPU) @ 0.
28/s (n=50)
nikolaPopper: 229 wallclock secs (226.87 usr + 0.00 sys = 226.87 CPU) @
0.22/s (n=50)
ciao
drieux
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