my %seen = (); # use hash for counting elements
my @doubles = grep {
  # if value not in seen, return 0 and add it 
  #    to %seen with start value of 1
  $seen{$_}++ 
} @array1;

foreach my $element ( @doubles ) {
  print "$element\n";
} # foreach @doubles
undef %seen;

[download]

disadvantage: if you have three or more values, they will be printed more than once, so the following solution might be more precise:

my %seen = ();
$seen{$_}++ for @array1;
for my $value ( keys %seen ) {
  print "$value\n" if $seen{$value} > 1;
} # for %seen

[download]

Best regards,
perl -e "s>>*F>e=>y)\*martinF)stronat)=>print,print v8.8.8.32.11.32"

In reply to Re: dup values by strat
in thread dup values by sanku

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