title: remove null items from a multidimensional array in C#
body: <p>Consider the following array:</p>
  
  <pre><code>object[,] output = new object[5,3]{{"A",false,123},{"B",false,12},{"C",true,456},{null,null,null},{null,null,null}};
  </code></pre>
  
  <p>What is the right code if we are going to remove null items?</p>