my %seen;
while(<>) {
  chomp;
  my ($k, $v) = split/\t/, $_;
  print("$k\t$v\n") if $seen{$k} eq $v;
  $seen{$k} = $v
}

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In reply to Re: extracting only those keys with uniq values in array list by salva
in thread extracting only those keys with uniq values in array list by v15

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