title: How to find the nth Index in a arrayList
body: <p>how to find the nth index in a arraylist
  ex: i hv a <code>List&lt;Character&gt; charList = new ArrayList&lt;Character&gt;(Arrays.asList('s', 'h','a','r','a','n'))</code></p>
  
  <pre><code>charList.indexOf('a'); 
  </code></pre>
  
  <p>always gives the <em>first</em> index of the <code>a</code>.
  How do I get the nth?</p>