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Postings from March 2002
From: "John W. Krahn" <krahnj@acm.org>
> Jenda Krynicky wrote:
> > And if you want 6 unique :
> >
> > my @myarr;
> > { # this block is here just to restrict the availability
> > # of %seen
> > my %seen;
> > while (@myarr < 6) {
> > my $num = 1 + int(rand 35);
> > push @myarr, $num
> > unless $seen{$num}++
> > }
> > }
> >
> > if you wanted that a bit longer:
> >
> > my @myarr;
> > { # this block is here just to restrict the availability
> > # of %seen
> > my %seen;
> > while (@myarr < 6) {
> > my $num = 1 + int(rand 35);
> > if (! $seen{$num}) {
> > push @myarr, $num;
> > $seen{$num} = 1
> > }
> > }
> > }
>
> Because of the nature of "randomness" this algorithm could take a long
> time to run.
It takes a random amout of time ;-)
> Better to shuffle an array of 35 numbers and pick six.
I always feel uneasy about shuffling. I never know whether I shuffled
sufficiently :-)
Jenda
=========== Jenda@Krynicky.cz == http://Jenda.Krynicky.cz ==========
There is a reason for living. There must be. I've seen it somewhere.
It's just that in the mess on my table ... and in my brain
I can't find it.
--- me
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