title: Calculate the sum of all two digits integers in an array
body: <p>I want to calculate the sum of all integers in an array which contain two digits. For example:</p>
  
  <pre><code>int[] arr1 = {1, 23, 4, 55};
  int[] arr2 = {2, 5, -66, 23};
  </code></pre>
  
  <p>The result for the first array should be <code>23 + 55 = 78</code>, while the result for the second array should be <code>-66 + 23 = -43</code>. How can I achieve this?</p>