title: What do I return if there is no numerical solution for my int returning method to find?
body: <p>This is my method for finding a single duplicate within an array. What should I return when an array has no duplicates?</p>
  
  <pre><code>public int findDuplicate(int[] array) {
      Arrays.sort(array);
      int duplicate = 0;
      for(int i = 0; i &lt; array.length; i++)
      {
          if(array[i] == duplicate)
          {
              return duplicate;
          }
          duplicate = array[i];
      }
      return ???;
  }
  </code></pre>