title: How to remove the last two occurrences of "-" character of a string?
body: <p>I have an array of strings that are formatted as such: </p>
  
  <pre><code>Ado-trastuzumab emtansine(HER2)02-22-2013
  </code></pre>
  
  <p>I would like to remove the last two "-" symbols only (from the date part of the original string) so that the name of the drug (Ado-trastuzumab emtansine) is not altered. Right now my regex removes all "-" symbols:</p>
  
  <pre><code>foreach my $string (@array) {
       $string =~ tr/-//d;
  }
  </code></pre>
  
  <p>I would like the output to instead be the following:</p>
  
  <pre><code>Ado-trastuzumab emtansine(HER2)02222013
  </code></pre>
  
  <p>Thanks for the help!</p>