title: Leading zeros in Ruby
body: <p>I have fields <code>hr</code> and <code>min</code>, both integers in my application. For <code>hr</code> field, if the user enters "1" I would like Rails to automatically pad it to "01" before saving it to the database. Also for the <code>min</code> field if the user enter "0" it should put in as "00".</p>
  
  <p>How can I do this?</p>