Although others have shown better solutions, The original post is nearly correct. The only problem is that the logic is backwards. 
#!/usr/bin/perl -w
use strict;
@ARGV = qw(a b c c d);    #remove the extra "c"

my @inputs = ();
my @values = ();

@inputs = @ARGV;

foreach my $elemnt (@inputs)
    {

#   if (grep {$_ ne $elemnt} @values)
    if (!grep {$_ eq $elemnt} @values)
        { push @values, $elemnt; }
    }

print "@values\n";

[download]
Bill

In reply to Re: Finding unique elements in inputs by BillKSmith
in thread Finding unique elements in inputs by Anonymous Monk

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