if(exists $hash{$_}){ # exists, so increment
    $hash{$_}++;
  }
  else{                 # doesn't exist, so set to 1
    $hash{$_} = 1;
  }

[download]
That can be more simply written as: 
  $hash{$_}++;

[download]
But I think that the OP wants to increment the hash key instead of the value: 
  $_++ while exists $hash{$_};
  $hash{$_}++;

[download]

In reply to Re^2: Perl Hash Files by jwkrahn
in thread Perl Hash Files by blundell

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