title: Find time difference between 10.30am to 7.30pm
body: <p>I have two textboxes in which the user will enter <code>startTime</code> and <code>endTime</code> in 12 hours format (Eg. 10:30 AM to 7:30 PM).</p>
  
  <p>On clicking the <code>Calculate</code> button, the user should get the difference between the two times inputted in textbox.</p>
  
  <p>I have not getting what datatype should handle this inputted text.</p>
  
  <p>I would really appreciate if someone could write few lines of program for me to understand better.</p>