You reduce randomness slightly my insisting on no duplication. Here's the code: 

sub distinct_random_int {
    my($num, $start,$end) = @_;
    my ($range, %nums) = $end - $start;
    if ($num < $range) {
        $nums{$start + int rand $range} = undef
            while keys(%nums) < $num;
        return keys %nums;
    }
    else {
        return;
    }
}

[download]
Storing in hash keys gets us uniqueness.

After Compline,
Zaxo

In reply to Re: How to generate different random numbers? by Zaxo
in thread How to generate distinct random numbers? by johnnywang

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