title: Comparing two arrays in C#
body: <pre><code>bool hasDuplicate = false;   
  int[] a = new int[] {1, 2, 3, 4};
  int[] b = new int[] { 5, 6, 1, 2, 7, 8 };
  </code></pre>
  
  <p>I need compare all elements of array A with element of array B and in case of a duplicate element in B, set hasDuplicate on TRUE.</p>