Wrong.

That will never pick the last element.

#!/usr/bin/perl

use strict;
use warnings 'all';

my @array = qw /first middle last/;

my $count =   0;
my $sec   = 100;
$SIG {ALRM} = sub {
    die "Ran for $sec seconds, trying $count times and failed.\n"
};
alarm $sec;

my $randomIndex;
do {
    $count ++;
    $randomIndex = rand $#array;
} until $array [$randomIndex] eq "last";

print "Success after $count tries.\n";

__END__
Ran for 100 seconds, trying 29495241 times and failed.
[download]

However, if we change the rand $#array to rand @array, we get:

Success after 2 tries.
[download]

or some other small number.

Abigail