title: PowerShell - filtering for unique values
body: <p>I have an input CSV file with a column containing information similar to the sample below:</p>
  
  <pre><code>805265
  995874
  805674
  984654
  332574
  339852
  </code></pre>
  
  <p>I'd like to extract unique values into a array based on the leading two characters, so using the above sample my result would be:</p>
  
  <p>80, 99, 98, 33</p>
  
  <p>How might I achieve this using PowerShell?</p>