title: Is it possible to write a ROT13 in one line?
body: <p>I have the following code which I would like to see as a oneliner. However, since I am very new to C#, I currently have no clue on how to do this...</p>
  
  <p>Code:</p>
  
  <pre><code>static string ROT13 (string input)
  {
      if (string.IsNullOrEmpty(input)) return input;
  
      char[] buffer = new char[input.Length];
  
      for (int i = 0; i &lt; input.Length; i++)
      {
          char c = input[i];
          if (c &gt;= 97 &amp;&amp; c &lt;= 122)
          {
              int j = c + 13;
              if (j &gt; 122) j -= 26;
              buffer[i] = (char)j;
          }
          else if (c &gt;= 65 &amp;&amp; c &lt;= 90)
          {
              int j = c + 13;
              if (j &gt; 90) j -= 26;
              buffer[i] = (char)j;
          }
          else
          {
              buffer[i] = (char)c;
          }
      }
      return new string(buffer);
  }
  </code></pre>
  
  <p>I am sorry for any inconvenience, just trying to learn more about this pretty language :)</p>