Leetcode: Edit Distance - 30 minutes talk

Oct. 20, 2017

Introduction

It is very interesting to spend time with my relative, a 22 year old in the city of Yichun. He is a computer science graduate from top universities in 2016, and he plans to take graduate admission test for a computer science master degree at the end of 2017.

30 minutes talk 

I am very open to the new idea. What I have to do is to continue to support my nephew for Canada sponsor application and then also help him to build a career in computer science field. 

It is very good for my nephew to get some skills to help his parents to manage a restaurant. I also prefer to encourage him to get more education instead of working in industry to work for some one else. 

I did spent 30 minutes to test his coding skills, and practiced my lecturing skills during my vacation, this is the second chat. He was getting better, I still had no idea how he learns and what is his learning style.  

Here are my notes I wrote on a piece of paper about the algorithm. The algorithm is documented in detail here. 

Highlights of talk 

I spent a few minutes to explain the possible deletion distance between two words "heat" and "hit". The minimum deletion distance is 3, including deletion of two chars ('e' and 'a') in the word "heat" and one deletion of chars ('i') in the word "hit".

The naive deletion distance 5 can be implemented by deletion of 3 chars in "heat" from second char to last char, and deletion of chars in "hit" from second char to last char.

I used two words "abc" and "defg" and explained the deletion distance of two words. The possible choice to delete a char each time is 2, and there are 7 choices, so it is 2⁷.

Actionable Item

Teaching was fun even though my nephew is a rookie in algorithm and data structure, he did not ask any question and surfed wechat while I was talking. He told me to continue and I was not sure if he understood the algorithm or not.