LeetCode - Preface - Day2

Let's get started

I read Shiroyama-san's blog post today and figured out it describes exactly what I think about the programming recently.

Since I used to major in business and recently switched my major to computer science, I always feel I'm lacking mathematical thinking. Once I confront with algorithm questions, I wanna see the solution ASAP instead of thinking...

But, I believe to keep solving questions (like more than 300 questions) will overcome the current situation, so I will solve 5 leet code questions today as day 2 of LeetCode 365 challenge.