playing golf, 
my @words  = ( ... );
my @common = qw|a and at|;

my %seen;
@seen{@common} = (1) x @common;
@words = grep { $_ = lc; ! $seen{$_}++ } sort @words;

[download]
:-) Autark

In reply to Re: List processing performance by autark
in thread List processing performance by Odud

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