September LeetCoding Challenge 2020

In this repository provided my Python solutions of September LeetCoding Challenge problems.

Introduction

In this repository provided my Python solutions of September LeetCoding Challenge problems.

• I highly recommend you to try and solve problems yourself before look at the solutions here.
• Solutions and approaches may be not optimal.
• All Solutions here are in Python 3.

Notes

For the following problems I was googling approaches:

• 57. Insert Interval (Hard) - Was close to solve it on my own, but not. Main error: I was trying to do it in a given list and struggle with removing fully overlapped intervals.
• 421. Maximum XOR of Two Numbers in an Array (Medium) - My first solution get Memory Limit Exceeded, second - Time Limit Exceeded. After several attempts I googled.
• 1041. Robot Bounded In Circle (Medium) - Watched how to optimize direction/position issue.
• 980. Unique Paths III (Hard) - Solved after watching several approaches/solutions.
• 399. Evaluate Division (Medium) - My solution passed 17/22 tests. I used one layer hashmap and it was the mistake. I wasn't be able to figure out what's wrong on my own.
• 713. Subarray Product Less Than K (Medium) - After several different solutions with Time Limit Exceeded status I watched how to optimize the best one.
• 139. Word Break (Medium) - My solution get Time Limit Exceeded. Watched how to make it right.

Week 1

№	Title	Solution	Difficulty
949.	Largest Time for Given Digits	Python	Easy
220.	Contains Duplicate III	Python	Medium
459.	Repeated Substring Pattern	Python	Easy
763.	Partition Labels	Python	Medium
1305.	All Elements in Two Binary Search Trees	Python	Medium
835.	Image Overlap	Python	Medium
290.	Word Pattern	Python	Easy

Week 2

№	Title	Solution	Difficulty
1022.	Sum of Root To Leaf Binary Numbers	Python	Easy
165.	Compare Version Numbers	Python	Medium
299.	Bulls and Cows	Python	Easy
152.	Maximum Product Subarray	Python	Medium
216.	Combination Sum III	Python	Medium
57.	Insert Interval	Python	Hard
198.	House Robber	Python	Easy

Week 3

№	Title	Solution	Difficulty
58.	Length of Last Word	Python	Easy
421.	Maximum XOR of Two Numbers in an Array	Python	Medium
1041.	Robot Bounded In Circle	Python	Medium
121.	Best Time to Buy and Sell Stock	Python	Easy
1291.	Sequential Digits	Python	Medium
980.	Unique Paths III	Python	Hard
1094.	Car Pooling	Python	Medium

Week 4

№	Title	Solution	Difficulty
229.	Majority Element II	Python	Medium
134.	Gas Station	Python	Medium
389.	Find the Difference	Python	Easy
179.	Largest Number	Python	Medium
495.	Teemo Attacking	Python	Medium
399.	Evaluate Division	Python	Medium
713.	Subarray Product Less Than K	Python	Medium

Week 5

№	Title	Solution	Difficulty
139.	Word Break	Python	Medium
41.	First Missing Positive	Python	Hard

License

The code is open-source and licensed under the MIT License.