zengtian006 / LeetCode

Array

#	Title	Time	Space	Remark
Leetcode 27	Remove Element	O(n)	O(1)	Two Pointer
Leetcode 26	Remove Duplicates from Sorted Array	O(n)	O(1)	Two Pointer
Leetcode 80	Remove Duplicates from Sorted Array II	O(n)	O(1)	Two Pointer
Leetcode 277	Find the Celebrity	O(n)	O(1)
Leetcode 189	Rotate Array	O(n)	O(1)
Leetcode 41	First Missing Positive	O(n	O(1)	Bucket Sort
Leetcode 299	Bulls and Cows	O(n)	O(n)
Leetcode 134	Gas Station	O(n)	O(1)
Leetcode 274	H-Index	O(n)	O(n)
Leetcode 275	H-Index II	O(logn)	O(1)	Binary Search
Leetcode 244	Shortest Word Distance II	O(n^2)	O(n)	Hashmap
Leetcode 245	Shortest Word Distance III	O(n^2)	O(n)
Leetcode 217	Contains Duplicate	O(n)	O(n)
Leetcode 219	Contains Duplicate II	O(n)	O(n)
Leetcode 220	Contains Duplicate III	O(n^2	O(1)
Leetcode 55	Jump Game	O(n)	O(1)	Greedy
Leetcode 45	Jump Game II	O(n)	O(1)	Greedy
Leetcode 403	Frog Jump	O(n)	O(n)	DFS
Leetcode 121	Best Time to Buy and Sell Stock	O(n)	O(1)
Leetcode 122	Best Time to Buy and Sell Stock II	O(n)	O(1)
Leetcode 123	Best Time to Buy and Sell Stock III	O(n)	O(n)
Leetcode 188	Best Time to Buy and Sell Stock IV	O(nk)*	O(nk)*	DP
Leetcode 309	Best Time to Buy and Sell Stock with Cooldown	O(n)	O(n)	DP
Leetcode 11	Container With Most Water	O(n)	O(1)	Two Pointer
Leetcode 42	Trapping Rain Water	O(n)	O(1)	Two Pointer
Leetcode 334	Increasing Triplet Subsequence	O(n)	O(1)
Leetcode 128	Longest Consecutive Sequence	O(n)	O(n)
Leetcode 287	Find the Duplicate Number	O(nlogn)	O(1)	Binary Search
Leetcode 289	Game of Life	O(mn)*	O(1)
Leetcode 57	Insert Interval	O(n)	O(1)
Leetcode 56	Merge Intervals	O(nlogn)	O(1)
Leetcode 986	Interval List Intersections	O(m+n)	O(1)
Leetcode 252	Meeting Rooms	O(nlogn)	O(1)
Leetcode 253	Meeting Rooms II	O(nlogn)	O(n)
Leetcode 352	Data Stream as Disjoint Intervals	O(n)	O(1)
Leetcode 239	Sliding Window Maximum	O(n)	O(n)
Leetcode 295	Find Median from Data Stream	O(nlogn)	O(n)
Leetcode 1093	Statistics from a Large Sample	O(1)	O(1)	295 follow up
Leetcode 53	Maximum Subarray	O(n)	O(n)
Leetcode 325	Maximum Size Subarray Sum Equals k	O(n)	O(n)
Leetcode 209	Minimum Size Subarray Sum	O(n)	O(1)	Two Pointer
Leetcode 238	Product of Array Except Self	O(n)	O(n)
Leetcode 152	Maximum Product Subarray	O(n)	O(1)
Leetcode 228	Summary Ranges	O(n)	O(1)
Leetcode 163	Missing Ranges	O(n)	O(1)
Leetcode 88	Merge Sorted Array	O(n)	O(1)	Two Pointer
Leetcode 75	Sort Colors	O(n)	O(1)	Two Pointer
Leetcode 283	Move Zeroes	O(n)	O(1)	Two Pointer
Leetcode 376	Wiggle Subsequence	O(n)	O(1)
Leetcode 280	Wiggle Sort	O(n)	O(1)
Leetcode 324	Wiggle Sort II	O(n)	O(n)
Leetcode 560	Subarray Sum Equals K	O(n)	O(n)
Leetcode 4	Median of Two Sorted Arrays	py	O(m+n)
Leetcode 1239	Maximum Length of a Concatenated String with Unique Characters	O(2^n)	O(n)
Leetcode 135	Candy	O(n)	O(n)
Leetcode 581	Shortest Unsorted Continuous Subarray	O(n)	O(n)
Leetcode 503	Next Greater Element II	O(n)	O(n)
Leetcode 496	Next Greater Element I	O(n)	O(n)
Leetcode 525	Contiguous Array	O(n)	O(n)
Leetcode 977	Squares of a Sorted Array	O(n)	O(n)

String

#	Title	Time	Space	Remark
Leetcode 28	Implement strStr()	O((n-l)l)*	O(1)
Leetcode 186	Reverse Words in a String II	O(n)	O(1)
Leetcode 205	Isomorphic Strings	O(n)	O(n)	HashMap
Leetcode 293	Flip Game	O(n)	O(1)
Leetcode 294	Flip Game II	O(n!)	O(n!)	BackTracking
Leetcode 290	Word Pattern	O(n)	O(n)	HashMap
Leetcode 242	Valid Anagram	O(nlogn)	O(1)
Leetcode 49	Group Anagrams	O(n)	O(n)
Leetcode 249	Group Shifted Strings	O(n)	O(n)
Leetcode 161	One Edit Distance	O(n)	O(1)
Leetcode 38	Count and Say	O(2^n)	O(1)
Leetcode 316	Remove Duplicate Letters	O(n)	O(1)
Leetcode 271	Encode and Decode Strings	O(n)	O(1)
Leetcode 168	Excel Sheet Column Title	O(n)	O(1)
Leetcode 171	Excel Sheet Column Number	O(n)	O(1)
Leetcode 13	Roman to Integer	O(1)	O(1)
Leetcode 12	Integer to Roman	O(n)	O(1)
Leetcode 273	Integer to English Words	O(n)	O(1)
Leetcode 157	Read N Characters Given Read4	O(n)	O(1)
Leetcode 158	Read N Characters Given Read4 II - Call multiple times	O(n)	O(n)
Leetcode 68	Text Justification	O(n)	O(n/kπ)
Leetcode 76	Minimum Window Substring	O(n)	O(n)	Sliding Window
Leetcode 3	Longest Substring Without Repeating Characters	O(n)	O(m)	Sliding Window
Leetcode 340	Longest Substring with At Most K Distinct Characters	O(n)	O(k)	Sliding Window
Leetcode 125	Valid Palindrome	O(n)	O(1)	Two Pointer
Leetcode 680	Valid Palindrome II	O(n)	O(n)	Two Pointer
Leetcode 5	Longest Palindromic Substring	O(n^2)	O(n^2)	DP
Leetcode 516	Longest Palindromic Subsequence	O(n^2)	O(n^2)	DP
Leetcode 214	Shortest Palindrome	O(n)	O(n)
Leetcode 336	Palindrome Pairs	O(nk^2)	O(n)
Leetcode 1246	Palindrome Removal	O(n^3)	O(n^2)
Leetcode 20	Valid Parentheses	O(n)	O(n)
Leetcode 1249	Minimum Remove to Make Valid Parentheses	O(n)	O(n)
Leetcode 22	Generate Parentheses	O(4^n)?	O(n)?	BackTracking
Leetcode 32	Longest Valid Parentheses	O(n)	O(n)	DP
Leetcode 241	Different Ways to Add Parentheses	?	?	Divide&Conquer
Leetcode 301	Remove Invalid Parentheses	O(n2^n)*	O(2^n)	BFS
Leetcode 678	Valid Parenthesis String	O(3^n)	O(n)	BFS
Leetcode 115	Distinct Subsequences	O(mn)	O(mn)	BackTracking
Leetcode 844	Backspace String Compare	O(m+n)	O(1)	Two Pointer
Leetcode 763	Partition Labels	O(n)	O(n)
Leetcode 616	Add Bold Tag in String	?	O(n)
Leetcode 97	Interleaving String	O(mn)	O(mn)
Leetcode 767	Reorganize String	O(nlogn)	O(n)
Leetcode 438	Find All Anagrams in a String	O(n)	O(n)
Leetcode 1156	Swap For Longest Repeated Character Substring	O(n)	O(n)

Math

#	Title	Time	Space	Remark
Leetcode 7	Reverse Integer	O(n)	O(1)
Leetcode 66	Plus One	O(n)	O(1)
Leetcode 8	String to Integer (atoi)	O(n)	O(1)
Leetcode 67	Add Binary	O(n)	O(1)
Leetcode 445	Add Two Numbers II	O(n)	O(n)
Leetcode 43	Multiply Strings	O(mn)*	O(m+n)
Leetcode 29	Divide Two Integers	O(n)	O(1)
Leetcode 69	Sqrt(x)	O(logn)	O(1)	Binary Search
Leetcode 50	Pow(x, n)	O(logn)	O(1) or O(logn)
Leetcode 367	Valid Perfect Square	O(logn)	O(1)	Binary Search
Leetcode 204	Count Primes	O(nloglogn)	O(n)
Leetcode 1	Two Sum	O(n)	O(n)
Leetcode 15	3Sum	O(n^2)	O(logn)~O(n)
Leetcode 18	4Sum	O(n^3)	O(logn)~O(n)
Leetcode 231	Power of Two	O(logn)	O(1)
Leetcode 202	Happy Number	O(logn)	O(logn)
Leetcode 263	Ugly Number	O(logn)	O(1)
Leetcode 264	Ugly Number II	O(n)	O(n)
Leetcode 223	Rectangle Area	O(1)	O(1)
Leetcode 670	Maximum Swap	O(n)	O(n)

Tree

#	Title	Time	Space	Remark
Leetcode 100	Same Tree	O(n)	O(logn)~O(n)
Leetcode 101	Symmetric Tree	O(n)	O(n)
Leetcode 226	Invert Binary Tree	O(n)	O(n)
Leetcode 257	Binary Tree Paths	O(n)	O(n)
Leetcode 112	Path Sum	O(n)	O(n)
Leetcode 113	Path Sum II	O(n)	O(n)
Leetcode 298	Binary Tree Longest Consecutive Sequence	O(n)	O(n)
Leetcode 111	Minimum Depth of Binary Tree	O(n^2)	O(n)
Leetcode 104	Maximum Depth of Binary Tree	O(n)	O(n)
Leetcode 110	Balanced Binary Tree	O(nlogn)	O(n)
Leetcode 124	Binary Tree Maximum Path Sum	O(n)	O(logn)	543
Leetcode 337	House Robber III	O(n)	O(n)
Leetcode 98	Validate Binary Search Tree	O(n)	O(n)
Leetcode 235	Lowest Common Ancestor of a Binary Search Tree	O(n)	O(n)	BST
Leetcode 236	Lowest Common Ancestor of a Binary Tree	O(n)	O(n)
Leetcode 108	Convert Sorted Array to Binary Search Tree	O(n)	O(n)	BST
Leetcode 173	Binary Search Tree Iterator	O(n)	O(n)	BST
Leetcode 230	Kth Smallest Element in a BST	O(n)	O(n)	BST
Leetcode 297	Serialize and Deserialize Binary Tree	O(n)	O(n)
Leetcode 285	Inorder Successor in BST	O(n)	O(H)	BST
Leetcode 270	Closest Binary Search Tree Value	O(n)	O(H)	BST
Leetcode 116	Populating Ne\xt Right Pointers in Each Node	O(n)	O(logn)
Leetcode 117	Populating Next Right Pointers in Each Node II	O(n)	O(n)
Leetcode 314	Binary Tree Vertical Order Traversal	O(nlogn)	O(n)
Leetcode 96	Unique Binary Search Trees	O(n^2)	O(n)	DP
Leetcode 105	Construct Binary Tree from Preorder and Inorder Traversal	O(n)	O(n)
Leetcode 106	Construct Binary Tree from Inorder and Postorder Traversal	O(n)	O(n)
Leetcode 889	Construct Binary Tree from Preorder and Postorder Traversal	O(n^2)	O(n)
Leetcode 1008	Construct Binary Search Tree from Preorder Traversal	O(n)	O(n)
Leetcode 199	Binary Tree Right Side View	O(n)	O(n)
Leetcode 545	Boundary of Binary Tree	O(n)	O(n)
Leetcode 366	Find Leaves of Binary Tree	O(n)	O(n)
Leetcode 863	All Nodes Distance K in Binary Tree	O(n)	O(n)
Leetcode 109	Convert Sorted List to Binary Search Tree	O(nlogn)	O(nlogn)
Leetcode 103	Binary Tree Zigzag Level Order Traversal	O(n)	O(n)
Leetcode 543	Diameter of Binary Tree	O(n)	O(logn)	124
Leetcode 428	Serialize and Deserialize N-ary Tree	O(n)	O(n)
Leetcode 987	Vertical Order Traversal of a Binary Tree	O(n)	O(n)
Leetcode 938	Range Sum of BST	O(n)	O(1)
Leetcode 450	Delete Node in a BST	O(logn)	O(logn)
Leetcode 549	Binary Tree Longest Consecutive Sequence II	__	__
Leetcode 1339	Maximum Product of Splitted Binary Tree	O(n)	O(n)

DFS & BFS

#	Title	Time	Space	Remark
Leetcode 200	Number of Islands	O(mn)	O(min(m,n))~O(mn)	BFS/DFS/Recursive
Leetcode 286	Walls and Gates	O(mn)	O(mn)	BFS/DFS
Leetcode 130	Surrounded Regions	O(mn)	O(mn)	DFS
Leetcode 339	Nested List Weight Sum	O(n)	O(n)	BFS
Leetcode 364	Nested List Weight Sum II	O(n)	O(n)	BFS
Leetcode 127	Word Ladder	O(n26^len)*	O(n)	BFS
Leetcode 126	Word Ladder II	O(n26^len)*	O(n+pl)*	BFS
Leetcode 695	Max Area of Island	O(mn)	O(mn)	BFS
Leetcode 490	The Maze	O(mn)	O(mn)	BFS
Leetcode 505	The Maze II	O(mnlog(mn))*	O(mn)	Heap
Leetcode 675	Cut Off Trees for Golf Event	O(mnlog(mn))*	O(mn)
Leetcode 1436	Destination City	__	__
Leetcode 332	Reconstruct Itinerary	__	__
Leetcode 787	Cheapest Flights Within K Stops	py	O(n)	Dijkstra
Leetcode 743	Network Delay Time	__	__	Dijkstra
Leetcode 994	Rotting Oranges	O(mn)	O(mn)	BFS
Leetcode 815	Bus Routes	__	__	BFS
Leetcode 638	Shopping Offers	__	__
Leetcode 1269	Number of Ways to Stay in the Same Place After Some Steps	__	__
Leetcode 329	Longest Increasing Path in a Matrix	__	__
Leetcode 1197	Minimum Knight Moves	__	__	BFS

Backtracking

#	Title	Time	Space
Leetcode 78	Subsets	O(n2^n)*	O(n)
Leetcode 90	Subsets II	O(n2^n)*	O(n)
Leetcode 77	Combinations	O(kCnk)*	O(k)?
Leetcode 39	Combination Sum	？	O(n)?
Leetcode 40	Combination Sum II	？	O(n)?
Leetcode 216	Combination Sum III	?	O(n)?
Leetcode 254	Factor Combinations	O(2^n)?	O(n)?
Leetcode 46	Permutations	O(n!)	O(n)
Leetcode 47	Permutations II	O(n!)?	?
Leetcode 31	Next Permutation	O(n)	O(1)
Leetcode 60	Permutation Sequence	O(n!)	O(n)
Leetcode 291	Word Pattern II	O(n(Cnm)*	On)
Leetcode 17	Letter Combinations of a Phone Number	O(3^n4^m*	O(n)
Leetcode 282	Expression Add Operators	O(n4^n)*	O(n)
Leetcode 140	Word Break II	O(n^2)	O(n)
Leetcode 351	Android Unlock Patterns	O(n!)	O(n)
Leetcode 51	N-Queens	O(n!)	O(n)
Leetcode 52	N-Queens II	O(n!)	O(n)
Leetcode 491	Increasing Subsequences	O(2^n)	O(2^n)
Leetcode 1192	Critical Connections in a Network	O(V+E)	O(n)
Leetcode 93	Restore IP Addresses	O(2^n)	O(2^n)

Backtracking 的时间复杂度

  # 在backtracking函数中，for 循环里有几种选择就是几的n次方, 最少的2^n 例如 下面这种情况是O(3^n)
  def bt(self,idx,n):
    for i in range(idx, n):
      self.bt()
      self.bt()
      self.bt()
  # 在bt函数中，如果每次for循环都是T-1，那么时间复杂度 是 O(2^n)
  def bt(self,idx,n):
    for i in range(idx, n):
      self.bt(i+1, n)
  # 在bt函数中，如果每次for循环都是重新遍历(不重复上一步），那么时间复杂度 是 O(n！)
  def bt(self,idx,n, visited):
    for i in range(n):
      if i not in visited:
        visited.add(i)
        self.bt(i+1, n, visited)
        visited.remove(i)

Dynamic Programming

#	Title	Time	Space	Remark
Leetcode 70	Climbing Stairs	O(n)	O(n)
Leetcode 62	Unique Paths	O(nm)*	O(nm)*	Same as 64
Leetcode 64	Minimum Path Sum	O(mn)*	O(mn)*
Leetcode 279	Perfect Squares	O(nn^0.5)*	O(n)	Same as 322,377
Leetcode 322	Coin Change	O(sn)*	O(s)
Leetcode 377	Combination Sum IV	O(sn)*	O(s)
Leetcode 139	Word Break	O(n^2)	O(n)
Leetcode 375	Guess Number Higher or Lower II	O(n^3)	O(n^2)
Leetcode 256	Paint House	O(n)	O(n)
Leetcode 265	Paint House II	O(nk^2)	O(nk)
Leetcode 72	Edit Distance	O(mn)	O(mn)
Leetcode 174	Dungeon Game	O(mn)	O(mn)
Leetcode 221	Maximal Square	O(mn)	O(mn)
Leetcode 85	Maximal Rectangle	O(mn)	O(mn)
Leetcode 312	Burst Balloons	O(n^3)	O(n^2)
Leetcode 198	House Robber	O(n)	O(n)
Leetcode 213	House Robber II	O(n)	O(n)
Leetcode 276	Paint Fence	O(n)	O(n)
Leetcode 91	Decode Ways	O(n)	O(n)
Leetcode 10	Regular Expression Matching	O(mn)	O(mn)
Leetcode 44	Wildcard Matching	O(mn)	O(mn)
Leetcode 1143	Longest Common Subsequence	O(mn)	O(mn)
Leetcode 472	Concatenated Words	O(nl)	O(l)
Leetcode 983	Minimum Cost For Tickets	O(n)	O(n)
Leetcode 368	Largest Divisible Subset	O(n^2)	O(n^2)

Binary Search

#	Title	Time	Space	Remark
Leetcode 278	First Bad Version	__	__
Leetcode 35	Search Insert Position	__	__
Leetcode 33	Search in Rotated Sorted Array	__	__
Leetcode 81	Search in Rotated Sorted Array II	__	__
Leetcode 153	Find Minimum in Rotated Sorted Array	__	__
Leetcode 154	Find Minimum in Rotated Sorted Array II	__	__
Leetcode 162	Find Peak Element	__	__
Leetcode 374	Guess Number Higher or Lower	__	__
Leetcode 34	Find First and Last Position of Element in Sorted Array	__	__
Leetcode 350	Intersection of Two Arrays II	__	__	Two Pointer/HashMap/BS
Leetcode 300	Longest Increasing Subsequence	O(nlogn)/O(n^2)	O(n)	BS/DP
Leetcode 354	Russian Doll Envelopes	O(nlogn)/O(n^2)	O(n)	BS/DP
Leetcode 658	Find K Closest Elements	__	__

Stack # Queue(or Heap)

#	Title	Time	Space	Remark
Leetcode 155	Min Stack	O(1)	O(n)
Leetcode 232	Implement Queue using Stacks	O(1)	O(n)	2 stacks
Leetcode 225	Implement Stack using Queues	O(1)~O(n)	O(n)	2 queues
Leetcode 150	Evaluate Reverse Polish Notation	O(n)	O(n)
Leetcode 71	Simplify Path	O(n)	O(n)
Leetcode 394	Decode String	O(n)	O(n)	2 stacks
Leetcode 224	Basic Calculator	O(n)	O(n)	2 stacks
Leetcode 227	Basic Calculator II	O(n)	O(n)
Leetcode 385	Mini Parser	O(n)	_O(n)klkj _
Leetcode 84	Largest Rectangle in Histogram	O(n)	O(n)
Leetcode 215	Kth Largest Element in an Array	O(nlogn)	O(n)
Leetcode 347	Top K Frequent Elements	O(n)	O(n)	bucket sort
Leetcode 692	Top K Frequent Words	O(nlogn)	O(n)	bucket sort
Leetcode 218	The Skyline Problem	O(nlogn)	O(n)
Leetcode 341	Flatten Nested List Iterator	O(n)	O(N)
Leetcode 373	Find K Pairs with Smallest Sums	O(klogk)	O(k)
Leetcode 378	Kth Smallest Element in a Sorted Matrix	O(klogk)	O(k)
Leetcode 1439	Find K Pairs with Smallest Sums of Matrix	__	__
Leetcode 739	Daily Temperatures	O(n)	O(n)
Leetcode 621	Task Scheduler	__	__

Matrix

#	Title	Time	Space	Remark
Leetcode 48	Rotate Image	__	__
Leetcode 54	Spiral Matrix	__	__
Leetcode 59	Spiral Matrix II	__	__
Leetcode 1439	Find the Kth Smallest Sum of a Matrix With Sorted Rows	__	__	Divide&Conquer
Leetcode 1311	Sparse Matrix Multiplication	__	__
Leetcode 1378	Kth Smallest Element in a Sorted Matrix	__	__
Leetcode 174	Search a 2D Matrix	__	__
Leetcode 1240	Search a 2D Matrix II	O(m+n)	O(1)
Leetcode 179	Word Search	__	__
Leetcode 1219	Path with Maximum Gold	__	__	Same as word search
Leetcode 1361	Bomb Enemy	__	__
Leetcode 136	Valid Sudoku	__	__
Leetcode 137	Sudoku Solver	__	__	BackTracking
Leetcode 909	Snakes and Ladders	__	__	BFS
Leetcode 1102	Path With Maximum Minimum Value	__	__	Greedy
Leetcode 296	Best Meeting Point	__	__	BFS
Leetcode 317	Shortest Distance from All Buildings	__	__	BFS

LinkedList

#	Title	Time	Space	Remark
Leetcode 206	Reverse Linked List	__	__
Leetcode 141	Linked List Cycle	__	__
Leetcode 24	Swap Nodes in Pairs	__	__
Leetcode 328	Odd Even Linked List	__	__
Leetcode 92	Reverse Linked List II	__	__
Leetcode 237	Delete Node in a Linked List	__	__
Leetcode 19	Remove Nth Node From End of List	__	__
Leetcode 83	Remove Duplicates from Sorted List	__	__
Leetcode 203	Remove Linked List Elements	__	__
Leetcode 82	Remove Duplicates from Sorted List II	__	__
Leetcode 369	Plus One Linked List	__	__
Leetcode 2	Add Two Numbers	__	__
Leetcode 160	Intersection of Two Linked Lists	__	__
Leetcode 21	Merge Two Sorted Lists	__	__
Leetcode 234	Palindrome Linked List	__	__
Leetcode 143	Reorder List	__	__
Leetcode 142	Linked List Cycle II	__	__
Leetcode 148	Sort List	__	__	Merge sort(Divide&Conquer)
Leetcode 25	Reverse Nodes in k-Group	__	__	Recursive
Leetcode 61	Rotate List	__	__
Leetcode 86	Partition List	__	__	Two Pointer
Leetcode 23	Merge k Sorted Lists	__	__	Merge sort
Leetcode 147	Insertion Sort List	__	__	Insertion sort

Toplogical Sort

#	Title	Time	Space
Leetcode 207	Course Schedule	__	__
Leetcode 210	Course Schedule II	__	__
Leetcode 269	Alien Dictionary	__	__

Bit Manipulation

#	Title	Time	Space	Remark
Leetcode 136	Single Number	__	__
Leetcode 318	Maximum Product of Word Lengths	__	__

Random

#	Title	Time	Space
Leetcode 384	Shuffle an Array	__	__
Leetcode 398	Random Pick Index	__	__
Leetcode 382	Linked List Random Node	__	__
Leetcode 380	Insert Delete GetRandom O(1)	__	__
Leetcode 381	Insert Delete GetRandom O(1) - Duplicates allowed	__	__

Graph

#	Title	Time	Space	Remark
Leetcode 133	Clone Graph	__	__
Leetcode 138	Copy List with Random Pointer	O(n)	O(n)
Leetcode 399	Evaluate Division	__	__	DFS
Leetcode 310	Minimum Height Trees	__	__	Topological Sort
Leetcode 1152. Analyze User Website Visit Pattern	__	__	Topological Sort

Union Find

#	Title	Time	Space	Remark
Leetcode 261	Graph Valid Tree	__	__	UF/DFS
Leetcode 323	Number of Connected Components in an Undirected Graph	__	__	UF/DFS
Leetcode 305	Number of Islands II	__	__

Trie

#	Title	Time	Space	Remark
Leetcode 208	Implement Trie (Prefix Tree)	__	__
Leetcode 211	Add and Search Word - Data structure design	__	__	DFS with Trie
Leetcode 212	Word Search II	__	__	BackTrakcing with Trie
Leetcode 642	Design Search Autocomplete System	__	__
Leetcode 588	Design In-Memory File System	__	__
Leetcode 635	Design Log Storage System	__	__

Design

#	Title	Time	Space	Remark
Leetcode 359	Logger Rate Limiter	__	__	Buffer
Leetcode 362	Design Hit Counter	__	__	Buffer
Leetcode 346	Moving Average from Data Stream	__	__
Leetcode 281	Zigzag Iterator	__	__
Leetcode 284	Peeking Iterator	__	__
Leetcode 251	Flatten 2D Vector	__	__
Leetcode 146	LRU Cache	__	__	Doubly liked list
Leetcode 460	LFU Cache	O(1)	O(n)	Doubly liked list
Leetcode 303	Range Sum Query - Immutable	__	__	PreSum
Leetcode 170	Two Sum III - Data structure design	__	__
Leetcode 348	Design Tic-Tac-Toe	__	__
Leetcode 353	Design Snake Game	__	__
Leetcode 355	Design Twitter	__	__	OOD
Leetcode 706	Design HashMap	__	__
Leetcode 622	Design Circular Queue	__	__
Leetcode 895	Maximum Frequency Stack	__	__
Leetcode 307	Range Sum Query - Mutable	O(logn)~O(n)	O(n)	Segment Trees

Non-Leetcode

Title	Time	Space	Remark
First Unique Number	__	__	Doubly liked list
Integer to Chinese	__	__
Print Nodes in Top View of Binary Tree	__	__
Bottom View of Binary Tree	__	__
K Decimal Addition	__	__

zengtian006 / LeetCode

README.md

Array

String

Math

Tree

DFS & BFS

Backtracking

Dynamic Programming

Binary Search

Stack # Queue(or Heap)

Matrix

LinkedList

Toplogical Sort

Bit Manipulation

Random

Graph

Union Find

Trie

Design

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zengtian006 / LeetCode

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README.md

Array

String

Math

Tree

DFS & BFS

Backtracking

Dynamic Programming

Binary Search

Stack # Queue(or Heap)

Matrix

LinkedList

Toplogical Sort

Bit Manipulation

Random

Graph

Union Find

Trie

Design

Non-Leetcode

About

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Resources

License

Releases

Packages 0

Languages

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