Practice

The NeetCode 150, in order, with a tracker

All 150 problems of the NeetCode 150 in NeetCode's order, grouped into its 18 categories: 28 easy, 101 medium, 21 hard. The week column is when the cracked.guide path schedules each one, two a week for the first 75 weeks.

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How tracking works

Sign up, link your LeetCode username, and solve problems under a public profile. Accepted NeetCode 150 problems on your profile are read from there and tick off the week they belong to; any other NeetCode problem you have not used yet counts too. The seven Premium problems link to their free versions on neetcode.io, and you can mark those solved yourself. Problem names and order follow neetcode.io.

Arrays & Hashing 9

#	Problem	Difficulty	Week
1	Contains Duplicate	Easy	1
2	Valid Anagram	Easy	1
3	Two Sum	Easy	2
4	Group Anagrams	Medium	2
5	Top K Frequent Elements	Medium	3
6	Encode and Decode Strings Premium on LeetCode	Medium	3
7	Product of Array Except Self	Medium	4
8	Valid Sudoku	Medium	4
9	Longest Consecutive Sequence	Medium	5

Two Pointers 5

#	Problem	Difficulty	Week
10	Valid Palindrome	Easy	5
11	Two Sum II Input Array Is Sorted	Medium	6
12	3Sum	Medium	6
13	Container With Most Water	Medium	7
14	Trapping Rain Water	Hard	7

Sliding Window 6

#	Problem	Difficulty	Week
15	Best Time to Buy And Sell Stock	Easy	8
16	Longest Substring Without Repeating Characters	Medium	8
17	Longest Repeating Character Replacement	Medium	9
18	Permutation In String	Medium	9
19	Minimum Window Substring	Hard	10
20	Sliding Window Maximum	Hard	10

Stack 6

#	Problem	Difficulty	Week
21	Valid Parentheses	Easy	11
22	Min Stack	Medium	11
23	Evaluate Reverse Polish Notation	Medium	12
24	Daily Temperatures	Medium	12
25	Car Fleet	Medium	13
26	Largest Rectangle In Histogram	Hard	13

Binary Search 7

#	Problem	Difficulty	Week
27	Binary Search	Easy	14
28	Search a 2D Matrix	Medium	14
29	Koko Eating Bananas	Medium	15
30	Find Minimum In Rotated Sorted Array	Medium	15
31	Search In Rotated Sorted Array	Medium	16
32	Time Based Key Value Store	Medium	16
33	Median of Two Sorted Arrays	Hard	17

Linked List 11

#	Problem	Difficulty	Week
34	Reverse Linked List	Easy	17
35	Merge Two Sorted Lists	Easy	18
36	Linked List Cycle	Easy	18
37	Reorder List	Medium	19
38	Remove Nth Node From End of List	Medium	19
39	Copy List With Random Pointer	Medium	20
40	Add Two Numbers	Medium	20
41	Find The Duplicate Number	Medium	21
42	LRU Cache	Medium	21
43	Merge K Sorted Lists	Hard	22
44	Reverse Nodes In K Group	Hard	22

Trees 15

#	Problem	Difficulty	Week
45	Invert Binary Tree	Easy	23
46	Maximum Depth of Binary Tree	Easy	23
47	Diameter of Binary Tree	Easy	24
48	Balanced Binary Tree	Easy	24
49	Same Tree	Easy	25
50	Subtree of Another Tree	Easy	25
51	Lowest Common Ancestor of a Binary Search Tree	Medium	26
52	Binary Tree Level Order Traversal	Medium	26
53	Binary Tree Right Side View	Medium	27
54	Count Good Nodes In Binary Tree	Medium	27
55	Validate Binary Search Tree	Medium	28
56	Kth Smallest Element In a Bst	Medium	28
57	Construct Binary Tree From Preorder And Inorder Traversal	Medium	29
58	Binary Tree Maximum Path Sum	Hard	29
59	Serialize And Deserialize Binary Tree	Hard	30

Heap / Priority Queue 7

#	Problem	Difficulty	Week
60	Kth Largest Element In a Stream	Easy	30
61	Last Stone Weight	Easy	31
62	K Closest Points to Origin	Medium	31
63	Kth Largest Element In An Array	Medium	32
64	Task Scheduler	Medium	32
65	Design Twitter	Medium	33
66	Find Median From Data Stream	Hard	33

Backtracking 10

#	Problem	Difficulty	Week
67	Subsets	Medium	34
68	Combination Sum	Medium	34
69	Combination Sum II	Medium	35
70	Permutations	Medium	35
71	Subsets II	Medium	36
72	Generate Parentheses	Medium	36
73	Word Search	Medium	37
74	Palindrome Partitioning	Medium	37
75	Letter Combinations of a Phone Number	Medium	38
76	N Queens	Hard	38

Tries 3

#	Problem	Difficulty	Week
77	Implement Trie Prefix Tree	Medium	39
78	Design Add And Search Words Data Structure	Medium	39
79	Word Search II	Hard	40

Graphs 13

#	Problem	Difficulty	Week
80	Number of Islands	Medium	40
81	Max Area of Island	Medium	41
82	Clone Graph	Medium	41
83	Walls And Gates Premium on LeetCode	Medium	42
84	Rotting Oranges	Medium	42
85	Pacific Atlantic Water Flow	Medium	43
86	Surrounded Regions	Medium	43
87	Course Schedule	Medium	44
88	Course Schedule II	Medium	44
89	Graph Valid Tree Premium on LeetCode	Medium	45
90	Number of Connected Components In An Undirected Graph Premium on LeetCode	Medium	45
91	Redundant Connection	Medium	46
92	Word Ladder	Hard	46

Advanced Graphs 6

#	Problem	Difficulty	Week
93	Network Delay Time	Medium	47
94	Reconstruct Itinerary	Hard	47
95	Min Cost to Connect All Points	Medium	48
96	Swim In Rising Water	Hard	48
97	Alien Dictionary Premium on LeetCode	Hard	49
98	Cheapest Flights Within K Stops	Medium	49

1-D Dynamic Programming 12

#	Problem	Difficulty	Week
99	Climbing Stairs	Easy	50
100	Min Cost Climbing Stairs	Easy	50
101	House Robber	Medium	51
102	House Robber II	Medium	51
103	Longest Palindromic Substring	Medium	52
104	Palindromic Substrings	Medium	52
105	Decode Ways	Medium	53
106	Coin Change	Medium	53
107	Maximum Product Subarray	Medium	54
108	Word Break	Medium	54
109	Longest Increasing Subsequence	Medium	55
110	Partition Equal Subset Sum	Medium	55

2-D Dynamic Programming 11

#	Problem	Difficulty	Week
111	Unique Paths	Medium	56
112	Longest Common Subsequence	Medium	56
113	Best Time to Buy And Sell Stock With Cooldown	Medium	57
114	Coin Change II	Medium	57
115	Target Sum	Medium	58
116	Interleaving String	Medium	58
117	Longest Increasing Path In a Matrix	Hard	59
118	Distinct Subsequences	Hard	59
119	Edit Distance	Medium	60
120	Burst Balloons	Hard	60
121	Regular Expression Matching	Hard	61

Greedy 8

#	Problem	Difficulty	Week
122	Maximum Subarray	Medium	61
123	Jump Game	Medium	62
124	Jump Game II	Medium	62
125	Gas Station	Medium	63
126	Hand of Straights	Medium	63
127	Merge Triplets to Form Target Triplet	Medium	64
128	Partition Labels	Medium	64
129	Valid Parenthesis String	Medium	65

Intervals 6

#	Problem	Difficulty	Week
130	Insert Interval	Medium	65
131	Merge Intervals	Medium	66
132	Non Overlapping Intervals	Medium	66
133	Meeting Rooms Premium on LeetCode	Easy	67
134	Meeting Rooms II Premium on LeetCode	Medium	67
135	Minimum Interval to Include Each Query	Hard	68

Math & Geometry 8

#	Problem	Difficulty	Week
136	Rotate Image	Medium	68
137	Spiral Matrix	Medium	69
138	Set Matrix Zeroes	Medium	69
139	Happy Number	Easy	70
140	Plus One	Easy	70
141	Pow(x, n)	Medium	71
142	Multiply Strings	Medium	71
143	Detect Squares	Medium	72

Bit Manipulation 7

#	Problem	Difficulty	Week
144	Single Number	Easy	72
145	Number of 1 Bits	Easy	73
146	Counting Bits	Easy	73
147	Reverse Bits	Easy	74
148	Missing Number	Easy	74
149	Sum of Two Integers	Medium	75
150	Reverse Integer	Medium	75

Questions

How many NeetCode 150 problems are LeetCode Premium?

7: Encode and Decode Strings, Walls And Gates, Graph Valid Tree, Number of Connected Components In An Undirected Graph, Alien Dictionary, Meeting Rooms, Meeting Rooms II. Each can be solved free on neetcode.io.

How long does the NeetCode 150 take?

At two problems a week, as on the cracked.guide path, 75 weeks. Full time, a few weeks to a couple of months.

How does cracked.guide track NeetCode progress?

Link your LeetCode username. Accepted NeetCode 150 problems on your public profile are read from there and count toward the week; Premium problems solved on neetcode.io you mark yourself.