title: Manhattan distance algorithm job interview question
body: <p>Given a set of <em>n</em> points in an X-Y plane, how can I determine if every point is at least separated by every other point by a Manhattan distance of 5 units in time less than O(n^2)?</p>
  
  <p>What is the best algorithm to implement this?</p>
  
  <p>Thank you.</p>