#!/usr/bin/perl

my $n = 1000;
my $cnt = 10;
my %ret;

for (my $i = 0; $i < $cnt; $i++) {
    my $r = int(rand()*$n);
    $r++ while exists $ret{$r};
    $ret{$r} = undef;
    $n--;
}

print "$cnt random indexes:\n";
foreach (keys %ret) {
    print "$_\n";
}