NeetCode 150 in Python with Tested Solutions

NeetCode 150 holds 150 problems (28 Easy, 100 Medium, 22 Hard). NeetCode 150 is a topic-by-topic roadmap from arrays and hashing through advanced graphs, built to pair with the NeetCode video explanations. Every problem generates a Python practice environment with a parametrized pytest suite and a tested reference solution. Generate the whole collection into the current directory:

lcpy gen -t neetcode-150

#	Problem	Difficulty	Solution
1	Two Sum	Easy	solution.py
2	Add Two Numbers	Medium	solution.py
3	Longest Substring Without Repeating Characters	Medium	solution.py
4	Median of Two Sorted Arrays	Hard	solution.py
5	Longest Palindromic Substring	Medium	solution.py
7	Reverse Integer	Medium	solution.py
10	Regular Expression Matching	Hard	solution.py
11	Container With Most Water	Medium	solution.py
15	3Sum	Medium	solution.py
17	Letter Combinations of a Phone Number	Medium	solution.py
19	Remove Nth Node From End of List	Medium	solution.py
20	Valid Parentheses	Easy	solution.py
21	Merge Two Sorted Lists	Easy	solution.py
22	Generate Parentheses	Medium	solution.py
23	Merge k Sorted Lists	Hard	solution.py
25	Reverse Nodes in k-Group	Hard	solution.py
33	Search in Rotated Sorted Array	Medium	solution.py
36	Valid Sudoku	Medium	solution.py
39	Combination Sum	Medium	solution.py
40	Combination Sum II	Medium	solution.py
42	Trapping Rain Water	Hard	solution.py
43	Multiply Strings	Medium	solution.py
45	Jump Game II	Medium	solution.py
46	Permutations	Medium	solution.py
48	Rotate Image	Medium	solution.py
49	Group Anagrams	Medium	solution.py
50	Pow(x, n)	Medium	solution.py
51	N-Queens	Hard	solution.py
53	Maximum Subarray	Medium	solution.py
54	Spiral Matrix	Medium	solution.py
55	Jump Game	Medium	solution.py
56	Merge Intervals	Medium	solution.py
57	Insert Interval	Medium	solution.py
62	Unique Paths	Medium	solution.py
66	Plus One	Easy	solution.py
70	Climbing Stairs	Easy	solution.py
72	Edit Distance	Hard	solution.py
73	Set Matrix Zeroes	Medium	solution.py
74	Search a 2D Matrix	Medium	solution.py
76	Minimum Window Substring	Hard	solution.py
78	Subsets	Medium	solution.py
79	Word Search	Medium	solution.py
84	Largest Rectangle in Histogram	Hard	solution.py
90	Subsets II	Medium	solution.py
91	Decode Ways	Medium	solution.py
97	Interleaving String	Medium	solution.py
98	Validate Binary Search Tree	Medium	solution.py
100	Same Tree	Easy	solution.py
102	Binary Tree Level Order Traversal	Medium	solution.py
104	Maximum Depth of Binary Tree	Easy	solution.py
105	Construct Binary Tree from Preorder and Inorder Traversal	Medium	solution.py
110	Balanced Binary Tree	Easy	solution.py
115	Distinct Subsequences	Hard	solution.py
121	Best Time to Buy and Sell Stock	Easy	solution.py
124	Binary Tree Maximum Path Sum	Hard	solution.py
125	Valid Palindrome	Easy	solution.py
127	Word Ladder	Hard	solution.py
128	Longest Consecutive Sequence	Medium	solution.py
130	Surrounded Regions	Medium	solution.py
131	Palindrome Partitioning	Medium	solution.py
133	Clone Graph	Medium	solution.py
134	Gas Station	Medium	solution.py
136	Single Number	Easy	solution.py
138	Copy List with Random Pointer	Medium	solution.py
139	Word Break	Medium	solution.py
141	Linked List Cycle	Easy	solution.py
143	Reorder List	Medium	solution.py
146	LRU Cache	Medium	solution.py
150	Evaluate Reverse Polish Notation	Medium	solution.py
152	Maximum Product Subarray	Medium	solution.py
153	Find Minimum in Rotated Sorted Array	Medium	solution.py
155	Min Stack	Medium	solution.py
167	Two Sum II - Input Array Is Sorted	Medium	solution.py
190	Reverse Bits	Easy	solution.py
191	Number of 1 Bits	Easy	solution.py
198	House Robber	Medium	solution.py
199	Binary Tree Right Side View	Medium	solution.py
200	Number of Islands	Medium	solution.py
202	Happy Number	Easy	solution.py
206	Reverse Linked List	Easy	solution.py
207	Course Schedule	Medium	solution.py
208	Implement Trie (Prefix Tree)	Medium	solution.py
210	Course Schedule II	Medium	solution.py
211	Design Add and Search Words Data Structure	Medium	solution.py
212	Word Search II	Hard	solution.py
213	House Robber II	Medium	solution.py
215	Kth Largest Element in an Array	Medium	solution.py
217	Contains Duplicate	Easy	solution.py
226	Invert Binary Tree	Easy	solution.py
230	Kth Smallest Element in a BST	Medium	solution.py
235	Lowest Common Ancestor of a Binary Search Tree	Medium	solution.py
238	Product of Array Except Self	Medium	solution.py
239	Sliding Window Maximum	Hard	solution.py
242	Valid Anagram	Easy	solution.py
252	Meeting Rooms	Easy	solution.py
253	Meeting Rooms II	Medium	solution.py
261	Graph Valid Tree	Medium	solution.py
268	Missing Number	Easy	solution.py
269	Alien Dictionary	Hard	solution.py
271	Encode and Decode Strings	Medium	solution.py
286	Walls And Gates	Medium	solution.py
287	Find the Duplicate Number	Medium	solution.py
295	Find Median from Data Stream	Hard	solution.py
297	Serialize and Deserialize Binary Tree	Hard	solution.py
300	Longest Increasing Subsequence	Medium	solution.py
309	Best Time to Buy and Sell Stock with Cooldown	Medium	solution.py
312	Burst Balloons	Hard	solution.py
322	Coin Change	Medium	solution.py
323	Number of Connected Components in an Undirected Graph	Medium	solution.py
329	Longest Increasing Path in a Matrix	Hard	solution.py
332	Reconstruct Itinerary	Hard	solution.py
338	Counting Bits	Easy	solution.py
347	Top K Frequent Elements	Medium	solution.py
355	Design Twitter	Medium	solution.py
371	Sum of Two Integers	Medium	solution.py
416	Partition Equal Subset Sum	Medium	solution.py
417	Pacific Atlantic Water Flow	Medium	solution.py
424	Longest Repeating Character Replacement	Medium	solution.py
435	Non-overlapping Intervals	Medium	solution.py
494	Target Sum	Medium	solution.py
518	Coin Change II	Medium	solution.py
543	Diameter of Binary Tree	Easy	solution.py
567	Permutation in String	Medium	solution.py
572	Subtree of Another Tree	Easy	solution.py
621	Task Scheduler	Medium	solution.py
647	Palindromic Substrings	Medium	solution.py
678	Valid Parenthesis String	Medium	solution.py
684	Redundant Connection	Medium	solution.py
695	Max Area of Island	Medium	solution.py
703	Kth Largest Element in a Stream	Easy	solution.py
704	Binary Search	Easy	solution.py
739	Daily Temperatures	Medium	solution.py
743	Network Delay Time	Medium	solution.py
746	Min Cost Climbing Stairs	Easy	solution.py
763	Partition Labels	Medium	solution.py
778	Swim in Rising Water	Hard	solution.py
787	Cheapest Flights Within K Stops	Medium	solution.py
846	Hand of Straights	Medium	solution.py
853	Car Fleet	Medium	solution.py
875	Koko Eating Bananas	Medium	solution.py
973	K Closest Points to Origin	Medium	solution.py
981	Time Based Key-Value Store	Medium	solution.py
994	Rotting Oranges	Medium	solution.py
1046	Last Stone Weight	Easy	solution.py
1143	Longest Common Subsequence	Medium	solution.py
1448	Count Good Nodes in Binary Tree	Medium	solution.py
1584	Min Cost to Connect All Points	Medium	solution.py
1851	Minimum Interval to Include Each Query	Hard	solution.py
1899	Merge Triplets to Form Target Triplet	Medium	solution.py
2013	Detect Squares	Medium	solution.py

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NeetCode 150 in Python with Tested Solutions