title: Prove a random generated number is uniform distributed
body: <p>I was asked this question in an interview.</p>
  
  <blockquote>
    <p>Given a random number generator to generate a number between [0,N), how
    to prove this number is uniform distributed.</p>
  </blockquote>
  
  <p>I am not sure how to approach this problem, any suggestion?</p>