http://www.perlmonks.org?node_id=981457


in reply to hash with both values and keys unique to each other

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;
}

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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.

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Re^2: hash with both values and keys unique to each other
by perlkhan77 (Acolyte) on Jul 12, 2012 at 19:19 UTC

    This is how I was able to do it. But it might not be a generalized solution 

    $seen{$chr1}++;
    $seen{$chr2}++;
    if (($seen{$chr1}>1)||($seen{$chr2}>1)){
        next;
    }    
    else{
          $hash_chr{$chr1}=$chr2;
          }

    [download]
[reply]
[d/l]

      Since your structure is

      loop {
  if (condition) {
    next;
  } # no else!
  other code;
}

      [download]

      You don't actually need the else block. Removing it will make your code look quite a bit more clean.

[reply]
[d/l]

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