This repository contains solutions and resources for LeetCode algorithm problems.

The solutions are derived from my own thinking and the discussion. They are cleaned and optimized carefully, thus more readable and understandable!

An excel table for quick review before interview is also provided in resources directory.

Also want to access all codes on your Android phone? Get APAS from GooglePlay here!

• Level Categorization: Easy, Middle and Hard.
• Problem Description and Tags on Top.
• Clear Solution Explanation.
• In-line Comment for Key Points.
• Different Solutions for Comparison.
• Test cases to help prove correctness.
• Importable and compilable with IntelliJ.

A table for all problems. Great for reference and review purpose!

This table has 5 sheets:

1. LeetCode Summary(1 ~ 154)
2. New Free Problems(155 ~ Latest)
3. New Problems in Book(156 ~ 159, 161, 163, 167, 170, 186)
4. Tips
5. Other Classic Problems

Each problem row has name, level, idea, code and frequency analysis.

• Frequency: derived from online resources and interview experience.
• Idea: the description of the general idea of the solution.
• Code: key steps in implementation.
• Tips: summary of tricks and tips appeared in solutions.
• New Problems: put into a single page because frequency is unknown.

Important and hard problems have bold title and key points are marked red.

LeetCode problems are not always enough. Some other popular or classic algorithm problems that worth taking a look are put in "src/main/java/com/freetymekiyan/algorithms/other/" directory for your reference.

Current resources are as followed:

1. Problems list of Clean Code Handbook published by LeetCode.
2. An .xlsx file for frequency and solutions.

1. Time and Space efficiency analysis.
2. Add new problems.
3. Add more resources.

1. LeetCode Online Judge

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Copyright (c) 2015 Yang Liu. http://freetymekiyan.github.io  
  
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