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Data Structures and Algorithms
Complexity Analysis
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Math & Bit Manipulation
Greedy Algorithms
Backtracking
Dynamic Programming
Summary
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Guide contents
Neetcode 250 (Java)
Arrays & Hashing
1.
217. Contains Duplicate
2.
242. Valid Anagram
3.
1. Two Sum
4.
49. Group Anagrams
5.
347. Top K Frequent Elements
6.
271. Encode and Decode Strings
7.
238. Product of Array Except Self
8.
36. Valid Sudoku
9.
122. Best Time to Buy and Sell Stock II
10.
128. Longest Consecutive Sequence
11.
1929. Concatenation of Array
12.
14. Longest Common Prefix
13.
27. Remove Element
14.
169. Majority Element
15.
304. Range Sum Query 2D - Immutable
16.
75. Sort Colors
17.
560. Subarray Sum Equals K
18.
705. Design HashSet
19.
706. Design HashMap
20.
912. Sort an Array
21.
229. Majority Element II
22.
41. First Missing Positive
Two Pointers
23.
125. Valid Palindrome
24.
167. Two Sum II - Input Array Is Sorted
25.
15. 3Sum
26.
11. Container With Most Water
27.
42. Trapping Rain Water
28.
1768. Merge Strings Alternately
29.
344. Reverse String
30.
88. Merge Sorted Array
31.
26. Remove Duplicates from Sorted Array
32.
680. Valid Palindrome II
33.
18. 4Sum
34.
189. Rotate Array
35.
881. Boats to Save People
Sliding Window
36.
121. Best Time to Buy and Sell Stock
37.
3. Longest Substring Without Repeating Characters
38.
424. Longest Repeating Character Replacement
39.
567. Permutation in String
40.
76. Minimum Window Substring
41.
239. Sliding Window Maximum
42.
219. Contains Duplicate II
43.
209. Minimum Size Subarray Sum
44.
658. Find K Closest Elements
Stack
45.
20. Valid Parentheses
46.
155. Min Stack
47.
150. Evaluate Reverse Polish Notation
48.
22. Generate Parentheses
49.
739. Daily Temperatures
50.
853. Car Fleet
51.
84. Largest Rectangle in Histogram
52.
682. Baseball Game
53.
225. Implement Stack using Queues
54.
232. Implement Queue using Stacks
55.
735. Asteroid Collision
56.
901. Online Stock Span
57.
71. Simplify Path
58.
394. Decode String
59.
895. Maximum Frequency Stack
Binary Search
60.
704. Binary Search
61.
74. Search a 2D Matrix
62.
875. Koko Eating Bananas
63.
153. Find Minimum in Rotated Sorted Array
64.
33. Search in Rotated Sorted Array
65.
981. Time Based Key-Value Store
66.
4. Median of Two Sorted Arrays
67.
35. Search Insert Position
68.
374. Guess Number Higher or Lower
69.
69. Sqrt(x)
70.
1011. Capacity To Ship Packages Within D Days
71.
81. Search in Rotated Sorted Array II
72.
410. Split Array Largest Sum
73.
1095. Find in Mountain Array
Linked List
74.
206. Reverse Linked List
75.
21. Merge Two Sorted Linked Lists
76.
141. Linked List Cycle Detection
77.
143. Reorder List
78.
19. Remove Node From End of Linked List
79.
138. Copy List With Random Pointer
80.
2. Add Two Numbers
81.
287. Find the Duplicate Number
82.
146. LRU Cache
83.
23. Merge K Sorted Linked Lists
84.
25. Reverse Nodes In K-Group
85.
92. Reverse Linked List II
86.
622. Design Circular Queue
87.
460. LFU Cache
Trees
88.
226. Invert Binary Tree
89.
104. Maximum Depth of Binary Tree
90.
543. Diameter of Binary Tree
91.
110. Balanced Binary Tree
92.
100. Same Binary Tree
93.
572. Subtree of Another Binary Tree
94.
235. Lowest Common Ancestor in Binary Search Tree
95.
102. Binary Tree Level Order Traversal
96.
199. Binary Tree Right Side View
97.
1448. Count Good Nodes in Binary Tree
98.
98. Validate Binary Search Tree
99.
230. Kth Smallest Integer in BST
100.
105. Construct Binary Tree From Preorder and Inorder Traversal
101.
124. Binary Tree Maximum Path Sum
102.
297. Serialize and Deserialize Binary Tree
103.
94. Binary Tree Inorder Traversal
104.
144. Binary Tree Preorder Traversal
105.
145. Binary Tree Postorder Traversal
106.
701. Insert into a Binary Search Tree
107.
450. Delete Node in a BST
108.
427. Construct Quad Tree
109.
337. House Robber III
110.
1325. Delete Leaves With a Given Value
Tries
111.
208. Implement Trie (Prefix Tree)
112.
211. Design Add and Search Words Data Structure
113.
212. Word Search II
114.
2707. Extra Characters in a String
Heap / Priority Queue
115.
703. Kth Largest Element in a Stream
116.
1046. Last Stone Weight
117.
973. K Closest Points to Origin
118.
215. Kth Largest Element in an Array
119.
621. Task Scheduler
120.
355. Design Twitter
121.
295. Find Median From Data Stream
122.
767. Reorganize String
123.
1834. Single-Threaded CPU
124.
1405. Longest Happy String
125.
1094. Car Pooling
126.
502. IPO
Backtracking
127.
78. Subsets
128.
39. Combination Sum
129.
40. Combination Sum II
130.
46. Permutations
131.
90. Subsets II
132.
79. Word Search
133.
131. Palindrome Partitioning
134.
17. Letter Combinations of a Phone Number
135.
51. N-Queens
136.
1863. Sum of All Subset XOR Totals
137.
77. Combinations
138.
47. Permutations II
139.
698. Partition to K Equal Sum Subsets
140.
473. Matchsticks to Square
141.
52. N-Queens II
142.
140. Word Break II
Graphs
143.
200. Number of Islands
144.
133. Clone Graph
145.
695. Max Area of Island
146.
417. Pacific Atlantic Water Flow
147.
130. Surrounded Regions
148.
994. Rotting Oranges
149.
286. Walls and Gates
150.
207. Course Schedule
151.
210. Course Schedule II
152.
684. Redundant Connection
153.
323. Number of Connected Components in an Undirected Graph
154.
261. Graph Valid Tree
155.
127. Word Ladder
156.
463. Island Perimeter
157.
953. Verifying an Alien Dictionary
158.
997. Find the Town Judge
159.
752. Open the Lock
160.
1462. Course Schedule IV
161.
721. Accounts Merge
162.
399. Evaluate Division
163.
310. Minimum Height Trees
Advanced Graphs
164.
332. Reconstruct Itinerary
165.
1584. Min Cost to Connect All Points
166.
743. Network Delay Time
167.
778. Swim in Rising Water
168.
269. Alien Dictionary
169.
787. Cheapest Flights Within K Stops
170.
1631. Path With Minimum Effort
171.
1489. Find Critical and Pseudo-Critical Edges in Minimum Spanning Tree
172.
2392. Build a Matrix With Conditions
173.
2709. Greatest Common Divisor Traversal
1-D Dynamic Programming
174.
70. Climbing Stairs
175.
746. Min Cost Climbing Stairs
176.
198. House Robber
177.
213. House Robber II
178.
5. Longest Palindromic Substring
179.
647. Palindromic Substrings
180.
91. Decode Ways
181.
322. Coin Change
182.
152. Maximum Product Subarray
183.
139. Word Break
184.
300. Longest Increasing Subsequence
185.
416. Partition Equal Subset Sum
186.
1137. N-th Tribonacci Number
187.
279. Perfect Squares
188.
377. Combination Sum IV
189.
343. Integer Break
190.
1406. Stone Game III
2-D Dynamic Programming
191.
62. Unique Paths
192.
1143. Longest Common Subsequence
193.
309. Best Time to Buy and Sell Stock with Cooldown
194.
518. Coin Change II
195.
494. Target Sum
196.
97. Interleaving String
197.
329. Longest Increasing Path in a Matrix
198.
115. Distinct Subsequences
199.
72. Edit Distance
200.
312. Burst Balloons
201.
10. Regular Expression Matching
202.
64. Minimum Path Sum
203.
63. Unique Paths II
204.
877. Stone Game
205.
1049. Last Stone Weight II
206.
1140. Stone Game II
Greedy
207.
53. Maximum Subarray
208.
55. Jump Game
209.
45. Jump Game II
210.
134. Gas Station
211.
846. Hand of Straights
212.
1899. Merge Triplets to Form Target Triplet
213.
763. Partition Labels
214.
678. Valid Parenthesis String
215.
860. Lemonade Change
216.
918. Maximum Sum Circular Subarray
217.
978. Longest Turbulent Subarray
218.
1871. Jump Game VII
219.
649. Dota2 Senate
220.
135. Candy
Intervals
221.
57. Insert Interval
222.
56. Merge Intervals
223.
435. Non-overlapping Intervals
224.
252. Meeting Rooms
225.
253. Meeting Rooms II
226.
1851. Minimum Interval to Include Each Query
227.
2402. Meeting Rooms III
Math & Geometry
228.
48. Rotate Image
229.
54. Spiral Matrix
230.
73. Set Matrix Zeroes
231.
202. Happy Number
232.
66. Plus One
233.
50. Pow(x, n)
234.
43. Multiply Strings
235.
2013. Detect Squares
236.
13. Roman to Integer
237.
168. Excel Sheet Column Title
238.
1071. Greatest Common Divisor of Strings
239.
2807. Insert Greatest Common Divisors in Linked List
240.
867. Transpose Matrix
Bit Manipulation
241.
136. Single Number
242.
191. Number of 1 Bits
243.
338. Counting Bits
244.
190. Reverse Bits
245.
268. Missing Number
246.
371. Sum of Two Integers
247.
7. Reverse Integer
248.
67. Add Binary
249.
201. Bitwise AND of Numbers Range
250.
3133. Minimum Array End
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Neetcode 250 (Java)
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Tries
Tries
Prefix trees for fast prefix lookup, wildcard search, and searching many words at once.
4 lessons
111.
208. Implement Trie (Prefix Tree)
112.
211. Design Add and Search Words Data Structure
113.
212. Word Search II
114.
2707. Extra Characters in a String
