Whiteboard White-knuckling – Part 4


Today I had J take another shot at whiteboarding an insertion sort. I ran into a problem. How do you tell someone their sort is correct or incorrect without sharing what the sort is actually meant to do? There are ways to create your own sorting algorithm, but is it still an insertion sort if it doesn’t have 2 arrays?

Communicating this dilemma to J, I decided to go old school. Paper prototyping old-school. I wrote out the word “Firefox” (the string he was sorting) and cut out the letters so that each letter was on its own piece of paper.

Then I demonstrated the sort. And I used 2 arrays to hold the unsorted list and the sorted list. Today I gave the slips of paper to J to review the insertion sort on his own. He’s whiteboarding the insertion sort now. Excited to see how this comes up. Glad to pinpoint specific points in communication and eventual understanding.

Whiteboard White-knuckling Part 3

Whiteboard White-knuckling Part 2

Whiteboard White-knuckling Part 1

Author: David Neely

Professional Software Developer. Technology and Web Coordinator at the University of Hawaii's Manoa Career Center.