There is a mistake in the fisher_yates_shuffle code above. The shuffle loop will never include the last element of the array.

--$i is calculated before entering the body. And rand($i + 1) will never return the value of $i.

The loop control that works is: 

  for ( my $i = @$array; $i; $i-- ) {

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This was originally posted as an Answer to the Categorized Question How do I shuffle an array?. It was removed from the CatQA section because it is not a good answer.

In reply to How do I shuffle an array? by BramVanOosterhout

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