title: How *(&arr + 1) - arr is working to give the array size
body: <pre><code>int arr[] = { 3, 5, 9, 2, 8, 10, 11 };      
  int arrSize = *(&amp;arr + 1) - arr;
  std::cout &lt;&lt; arrSize;
  </code></pre>
  <p>I am not able to get how this is working. So anyone can help me with this.</p>