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LeetCode 150

Top interview questions for technical preparation.

150Graphs - BFS

2038. Nearest Exit from Entrance in Maze
SolutionMEDIUM
1036. Rotting Oranges
SolutionMEDIUM

150Array / String

88. Merge Sorted Array
SolutionEASY
27. Remove Element
SolutionEASY
26. Remove Duplicates from Sorted Array
SolutionEASY
80. Remove Duplicates from Sorted Array II
SolutionMEDIUM
169. Majority Element
SolutionEASY
189. Rotate Array
SolutionMEDIUM
121. Best Time to Buy and Sell Stock
SolutionEASY
122. Best Time to Buy and Sell Stock II
SolutionMEDIUM
55. Jump Game
SolutionMEDIUM
45. Jump Game II
SolutionMEDIUM
274. H-Index
SolutionMEDIUM
380. Insert Delete GetRandom O(1)
SolutionMEDIUM
238. Product of Array Except Self
SolutionMEDIUM
134. Gas Station
SolutionMEDIUM
135. Candy
SolutionHARD
42. Trapping Rain Water
SolutionHARD
13. Roman to Integer
SolutionEASY
12. Integer to Roman
SolutionMEDIUM
58. Length of Last Word
SolutionEASY
14. Longest Common Prefix
SolutionEASY
151. Reverse Words in a String
SolutionMEDIUM
6. Zigzag Conversion
SolutionMEDIUM
28. Find the Index of the First Occurrence in a String
SolutionEASY
68. Text Justification
SolutionHARD

150Two Pointers

125. Valid Palindrome
SolutionEASY
392. Is Subsequence
SolutionEASY
167. Two Sum II - Input Array Is Sorted
SolutionMEDIUM
11. Container With Most Water
SolutionMEDIUM
15. 3Sum
SolutionMEDIUM

150Sliding Window

209. Minimum Size Subarray Sum
SolutionMEDIUM
3. Longest Substring Without Repeating Characters
SolutionMEDIUM
30. Substring with Concatenation of All Words
SolutionHARD
76. Minimum Window Substring
SolutionHARD

150Matrix

36. Valid Sudoku
SolutionMEDIUM
54. Spiral Matrix
SolutionMEDIUM
48. Rotate Image
SolutionMEDIUM
73. Set Matrix Zeroes
SolutionMEDIUM
289. Game of Life
SolutionMEDIUM

150Hashmap

383. Ransom Note
SolutionEASY
205. Isomorphic Strings
SolutionEASY
290. Word Pattern
SolutionEASY
242. Valid Anagram
SolutionEASY
49. Group Anagrams
SolutionMEDIUM
1. Two Sum
SolutionEASY
202. Happy Number
SolutionEASY
219. Contains Duplicate II
SolutionEASY
128. Longest Consecutive Sequence
SolutionMEDIUM

150Intervals

228. Summary Ranges
SolutionEASY
56. Merge Intervals
SolutionMEDIUM
57. Insert Interval
SolutionMEDIUM
452. Minimum Number of Arrows to Burst Balloons
SolutionMEDIUM

150Stack

20. Valid Parentheses
SolutionEASY
71. Simplify Path
SolutionMEDIUM
155. Min Stack
SolutionMEDIUM
150. Evaluate Reverse Polish Notation
SolutionMEDIUM
224. Basic Calculator
SolutionHARD

150Linked List

141. Linked List Cycle
SolutionEASY
2. Add Two Numbers
SolutionMEDIUM
21. Merge Two Sorted Lists
SolutionEASY
138. Copy List with Random Pointer
SolutionMEDIUM
92. Reverse Linked List II
SolutionMEDIUM
25. Reverse Nodes in k-Group
SolutionHARD
19. Remove Nth Node From End of List
SolutionMEDIUM
82. Remove Duplicates from Sorted List II
SolutionMEDIUM
61. Rotate List
SolutionMEDIUM
86. Partition List
SolutionMEDIUM
146. LRU Cache
SolutionMEDIUM

150Binary Tree General

104. Maximum Depth of Binary Tree
SolutionEASY
100. Same Tree
SolutionEASY
226. Invert Binary Tree
SolutionEASY
101. Symmetric Tree
SolutionEASY
105. Construct Binary Tree from Preorder and Inorder Traversal
SolutionMEDIUM
106. Construct Binary Tree from Inorder and Postorder Traversal
SolutionMEDIUM
117. Populating Next Right Pointers in Each Node II
SolutionMEDIUM
114. Flatten Binary Tree to Linked List
SolutionMEDIUM
112. Path Sum
SolutionEASY
129. Sum Root to Leaf Numbers
SolutionMEDIUM
124. Binary Tree Maximum Path Sum
SolutionHARD
173. Binary Search Tree Iterator
SolutionMEDIUM
222. Count Complete Tree Nodes
SolutionEASY
236. Lowest Common Ancestor of a Binary Tree
SolutionMEDIUM

150Binary Tree BFS

199. Binary Tree Right Side View
SolutionMEDIUM
637. Average of Levels in Binary Tree
SolutionEASY
102. Binary Tree Level Order Traversal
SolutionMEDIUM
103. Binary Tree Zigzag Level Order Traversal
SolutionMEDIUM

150Binary Search Tree

530. Minimum Absolute Difference in BST
SolutionEASY
230. Kth Smallest Element in a BST
SolutionMEDIUM
98. Validate Binary Search Tree
SolutionMEDIUM

150Graph General

200. Number of Islands
SolutionMEDIUM
130. Surrounded Regions
SolutionMEDIUM
133. Clone Graph
SolutionMEDIUM
399. Evaluate Division
SolutionMEDIUM
207. Course Schedule
SolutionMEDIUM
210. Course Schedule II
SolutionMEDIUM

150Graph BFS

945. Snakes and Ladders
SolutionMEDIUM
433. Minimum Genetic Mutation
SolutionMEDIUM
127. Word Ladder
SolutionHARD

150Trie

208. Implement Trie (Prefix Tree)
SolutionMEDIUM
211. Design Add and Search Words Data Structure
SolutionMEDIUM
212. Word Search II
SolutionHARD

150Backtracking

17. Letter Combinations of a Phone Number
SolutionMEDIUM
77. Combinations
SolutionMEDIUM
46. Permutations
SolutionMEDIUM
39. Combination Sum
SolutionMEDIUM
52. N-Queens II
SolutionHARD
22. Generate Parentheses
SolutionMEDIUM
79. Word Search
SolutionMEDIUM

150Divide & Conquer

108. Convert Sorted Array to Binary Search Tree
SolutionEASY
148. Sort List
SolutionMEDIUM
772. Construct Quad Tree
SolutionMEDIUM
23. Merge k Sorted Lists
SolutionHARD

150Kadane's Algorithm

53. Maximum Subarray
SolutionMEDIUM
954. Maximum Sum Circular Subarray
SolutionMEDIUM

150Binary Search

35. Search Insert Position
SolutionEASY
74. Search a 2D Matrix
SolutionMEDIUM
162. Find Peak Element
SolutionMEDIUM
33. Search in Rotated Sorted Array
SolutionMEDIUM
34. Find First and Last Position of Element in Sorted Array
SolutionMEDIUM
153. Find Minimum in Rotated Sorted Array
SolutionMEDIUM
4. Median of Two Sorted Arrays
SolutionHARD

150Heap

215. Kth Largest Element in an Array
SolutionMEDIUM
502. IPO
SolutionHARD
373. Find K Pairs with Smallest Sums
SolutionMEDIUM
295. Find Median from Data Stream
SolutionHARD

150Bit Manipulation

67. Add Binary
SolutionEASY
190. Reverse Bits
SolutionEASY
191. Number of 1 Bits
SolutionEASY
136. Single Number
SolutionEASY
137. Single Number II
SolutionMEDIUM
201. Bitwise AND of Numbers Range
SolutionMEDIUM

150Math

9. Palindrome Number
SolutionEASY
66. Plus One
SolutionEASY
172. Factorial Trailing Zeroes
SolutionMEDIUM
69. Sqrt(x)
SolutionEASY
50. Pow(x, n)
SolutionMEDIUM
149. Max Points on a Line
SolutionHARD

1501D DP

70. Climbing Stairs
SolutionEASY
198. House Robber
SolutionMEDIUM
139. Word Break
SolutionMEDIUM
322. Coin Change
SolutionMEDIUM
300. Longest Increasing Subsequence
SolutionMEDIUM

150Multidimensional DP

120. Triangle
SolutionMEDIUM
64. Minimum Path Sum
SolutionMEDIUM
63. Unique Paths II
SolutionMEDIUM
5. Longest Palindromic Substring
SolutionMEDIUM
97. Interleaving String
SolutionMEDIUM
72. Edit Distance
SolutionMEDIUM
123. Best Time to Buy and Sell Stock III
SolutionHARD
188. Best Time to Buy and Sell Stock IV
SolutionHARD
221. Maximal Square
SolutionMEDIUM

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