title: How to calculate distance between two cities using google maps api V3
body: <p>How to calculate the driving distance ?</p>
  
  <p>I'm unable to find a working example, can anybody help me ?</p>
  
  <p>Thank you.</p>
  
  <p>EDIT: 
  More info:</p>
  
  <p>I have two text inputs to type the cities. On change I just want to display/update the distance in another div.</p>