title: Find non-adjacent repeating values in tuple in PIG
body: <p>Is there a way to discard tuples that have repeating non adjacent (not next to each other) values?</p>
  
  <p>Given list of tuples:</p>
  
  <pre><code>(1,2,3)
  
  (1,1,2)
  
  (1,2,1)
  
  (2,2,1,2)
  </code></pre>
  
  <p>Want these:</p>
  
  <pre><code>(1,2,3)
  
  (1,1,2)
  </code></pre>
  
  <p>Don't want these:</p>
  
  <pre><code>(1,2,1)
  
  (2,2,1,2) 
  </code></pre>