Review medium and hard level hashtable algorithm

Oct. 3, 2018

Introduction

It is a good idea to share all my practice on Leetcode discuss, medium level and hard level.

Algorithms to review

I solved 4 hard level, 6 medium level algorithm.

Medium level

    3   longest substring without repeating characters
  18   4 sum
  49   Group anagrams
  94   Binary tree inorder traversal
187   Repeated DNA sequences
347   Top k frequent elements
554   Brick wall

Hard level

  37   Sudoku Solver
  76   Minimum window substring
  85   Maximal rectangle

726   Number of atoms

Actionable Items

I reviewed the algorithm 726 Number of atoms. It is so complicated. I think that I should spend time to work on easy level and medium level algorithms first. 

I shared my C# code of Leetcode 37 Sudoku solver, here is discuss link.