title: C# compiler error: "not all code paths return a value"
body: <p>I'm trying to write code that returns whether or not a given integer is divisible evenly by 1 to 20, <br>but I keep receiving the following error: </p>
  
  <blockquote>
    <p>error CS0161: 'ProblemFive.isTwenty(int)': not all code paths return a value</p>
  </blockquote>
  
  <p>Here is my code: </p>
  
  <pre><code>public static bool isTwenty(int num)
  {
      for(int j = 1; j &lt;= 20; j++)
      {
          if(num % j != 0)
          {
              return false;
          }
          else if(num % j == 0 &amp;&amp; num == 20)
          {
              return true;
          }
      }
  }
  </code></pre>