A quick way to get a list of unique values is to store them as keys in a hash. 
my @ary = qw(a a b c d e f f f g h i i j k l l);

my %unique = map { $_, 1 } @ary;
my @randUnique = sort { rand(1) <=> rand(1) } keys %unique;

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joecamel

In reply to Re: random index in array - no duplicates by joecamel
in thread random index in array - no duplicates by emilford

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