Assuming your question is "How to keep the values of a hash unique?", the answer is, well, two hashes:

my (%hash, %rhash);

while (<>) {
  chomp;
  my ($key, $val) = split(/\t/, $_, 2);

  next if (exists $hash{$key} or exists $rhash{$val});
  $hash{$key} = $val;
  $rhash{$val} = 1;
}

[download]

Of course, there will be some manual housekeeping of the second hash. You could make it look nicer by creating an object that mimics a hash.

In reply to Re: hash with both values and keys unique to each other by Anonymous Monk
in thread hash with both values and keys unique to each other by perlkhan77

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