Introduction
I like to work on 20 hard level algorithms based on the blog in a week. The idea is to get to know more hard level algorithm, so I can get very busy thinking about the algorithm, read various ideas to solve the problem.
I can use the lunch break of each weekday, and then give the hard level algorithm a nickname to help me explore new algorithm.
Do not go to lunch break until I have a hard level algorithm.
Here are the hard level algorithm:
Leetcode 233, 239, 265, 269, 273, 282, 281, 291, 302, 308, 312, 317, 329, 330, 336, 340, 352, 354, 363.
