Leetcode

My solutions and thoughts in Leetcode🔑

Solved: 155/701

Language: Java

Classification	Problem	Difficulty
Stack	636. Exclusive Time of Functions	Medium
Backtracking	282. Expression Add Operators	Hard
Grid	695. Max Area of Island	Easy
Grid	750. Number Of Corner Rectangles	Medium
Graph	261. Graph Valid Tree	Medium
Graph	210. Course Schedule II	Medium
Graph	79. Word Search	Medium
Graph	286. Walls and Gates	Medium
Graph	133. Clone Graph	Medium
Graph	200. Number of Islands	Medium
Database	597. Friend Requests I: Overall Acceptance Rate	Easy
Database	602. Friend Requests II: Who Has the Most Friends	Medium
DP	265. Paint House II	Hard
DP	85. Maximal Rectangle	Hard
DP	639. Decode Ways II	Hard
DP	44. Wildcard Matching	Hard
DP	673. Number of Longest Increasing Subsequence	Medium
DP	764. Largest Plus Sign	Medium
DP	221. Maximal Square	Medium
DP	377. Combination Sum IV	Medium
DP	714. Best Time to Buy and Sell Stock with Transaction Fee	Medium
DP	494. Target Sum	Medium
DP	139. Word Break	Medium
DP	10. Regular Expression Matching	Hard
DP	689. Maximum Sum of 3 Non-Overlapping Subarrays	Hard
DP	674. Longest Continuous Increasing Subsequence	Easy
DP	91. Decode Ways	Medium
DP	121. Best Time to Buy and Sell Stock	Easy
Basic	721. Accounts Merge	Medium
Basic	208. Implement Trie (Prefix Tree)	Medium
Basic	398. Random Pick Index	Medium
Basic	215. Kth Largest Element in an Array	Medium
Basic	56. Merge Intervals	Medium
Basic	69. Sqrt(x)	Easy
Basic	278. First Bad Version	Easy
Basic	252. Meeting Rooms	Easy
Basic	38. Count and Say	Easy
Hash	128. Longest Consecutive Sequence	Hard
Hash	525. Contiguous Array	Medium
Hash	380. Insert Delete GetRandom O(1)	Medium
Hash	523. Continuous Subarray Sum	Medium
Hash	1.Two Sum	Easy
List	35. Search Insert Position	Easy
List	4. Median of Two Sorted Arrays	Hard
List	2. Add Two Numbers	Medium
List	410. Split Array Largest Sum	Hard
List	25. Reverse Nodes in k-Group	Hard
List	57. Insert Interval	Hard
List	80. Remove Duplicates from Sorted Array II	Medium
List	90. Subsets II	Medium
List	209. Minimum Size Subarray Sum	Medium
List	75. Sort Colors	Medium
List	78. Subsets	Medium
List	341. Flatten Nested List Iterator	Medium
List	23. Merge k Sorted Lists	Hard
List	158. Read N Characters Given Read4 II - Call multiple times	Hard
List	311. Sparse Matrix Multiplication	Medium
List	33. Search in Rotated Sorted Array	Medium
List	234. Palindrome Linked List	Easy
List	157. Read N Characters Given Read4	Easy
List	88. Merge Sorted Array	Easy
List	148. Sort	Medium
List	15. 3Sum	Medium
List	283. Move Zeroes	Easy
List	26. Remove Duplicates from Sorted Array	Easy
List	325. Maximum Size Subarray Sum Equals k	Medium
Math	218. The Skyline Problem	Hard
Math	277. Find the Celebrity	Medium
Math	275. H-Index II	Medium
Math	274. H-Index	Medium
Math	334. Increasing Triplet Subsequence	Medium
Math	554. Brick Wall	Medium
Math	477. Total Hamming Distance	Medium
Math	670. Maximum Swap	Medium
Math	50. Pow(x,n)	Medium
Math	253. Meeting Rooms II	Medium
Math	168. Excel Sheet Column Title	Easy
Math	621. Task Scheduler	Medium
String	3. Longest Substring Without Repeating Characters	Medium
String	67. Add Binary	Easy
String	745. Prefix and Suffix Search	Hard
String	68. Text Justification	Hard
String	269. Alien Dictionary	Hard
String	127. Word Ladder	Hard
String	642. Design Search Autocomplete System	Hard
String	71. Simplify Path	Medium
String	409. Longest Palindrome	Easy
String	43. Multiply Strings	Medium
String	161. One Edit Distance	Medium
String	211. Add and Search Word - Data structure design	Medium
String	76. Minimum Window Substring	Hard
String	273. Integer to English Words	Hard
String	125. Valid Palindrome	Easy
String	301. Remove Invalid Parentheses	Hard
String	17. Letter Combinations of a Phone Number	Medium
String	680. Valid Palindrome II	Easy
String	28. Implement strStr()	Easy
String	300. Longest Increasing Subsequence	Medium
String	388. Longest Absolute File Path	Medium
String	647. Palindromic Substrings	Medium
String	657. Judge Route Circle	Easy
Tree	117. Populating Next Right Pointers in Each Node II	Medium
Tree	102. Binary Tree Level Order Traversal	Medium
Tree	236. Lowest Common Ancestor of a Binary Tree	Medium
Tree	98. Validate Binary Search Tree	Medium
Tree	285. Inorder Successor in BST	Medium
Tree	173. Binary Search Tree Iterator	Medium
Tree	297. Serialize and Deserialize Binary Tree	Hard
Tree	257. Binary Tree Paths	Easy
Tree	404. Sum of Left Leaves	Easy
Tree	572. Subtree of Another Tree	Easy
Tree	314. Binary Tree Vertical Order Traversal	Medium
Tree	637. Average of Levels in Binary Tree	Easy
Tree	235. Lowest Common Ancestor of a Binary Search Tree	Easy
Tree	653. Two Sum IV - Input is a BST	Easy
Tree	617. Merge Two Binary Trees	Easy
Tree	543. Diameter of Binary Tree	Easy