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Random and Sampling

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cocoder39 edited this page Jan 17, 2021 · 8 revisions

Random

384. Shuffle an Array
528. Random Pick with Weight

Rejection Sampling

470. Implement Rand10() Using Rand7()
478. Generate Random Point in a Circle

Reservoir Sampling

398. Random Pick Index
382. Linked List Random Node

Toggle table of contents Pages 578

Home
1. Two Sum
10. Regular Expression Matching
100. Same Tree
1004. Max Consecutive Ones III
101. Symmetric Tree
102. Binary Tree Level Order Traversal
1024. Video Stitching
103. Binary Tree Zigzag Level Order Traversal
104. Maximum Depth of Binary Tree
1041. Robot Bounded In Circle
1042. Flower Planting With No Adjacent
1047. Remove All Adjacent Duplicates In String
1048. Longest String Chain
105. Construct Binary Tree from Preorder and Inorder Traversal
1058. Minimize Rounding Error to Meet Target
106. Construct Binary Tree from Inorder and Postorder Traversal
1060. Missing Element in Sorted Array
107. Binary Tree Level Order Traversal II
108. Convert Sorted Array to Binary Search Tree
109. Convert Sorted List to Binary Search Tree
1091. Shortest Path in Binary Matrix
1094. Car Pooling
11. Container With Most Water
110. Balanced Binary Tree
1109. Corporate Flight Bookings
111. Minimum Depth of Binary Tree
1110. Delete Nodes And Return Forest
1114. Print in Order
1115. Print FooBar Alternately
1116. Print Zero Even Odd
1117. Building H2O
112. Path Sum
113. Path Sum II
1130. Minimum Cost Tree From Leaf Values
114. Flatten Binary Tree to Linked List
1140. Stone Game II
1143. Longest Common Subsequence
1146. Snapshot Array
115. Distinct Subsequences
1153. String Transforms Into Another String
116. Populating Next Right Pointers in Each Node
1162. As Far from Land as Possible
1166. Design File System
117. Populating Next Right Pointers in Each Node II
1188. Design Bounded Blocking Queue
1192. Critical Connections in a Network
1195. Fizz Buzz Multithreaded
1197. Minimum Knight Moves
120. Triangle
1202. Smallest String With Swaps
1206. Design Skiplist
1209. Remove All Adjacent Duplicates in String II
121. Best Time to Buy and Sell Stock
1216. Valid Palindrome III
122. Best Time to Buy and Sell Stock II
1226. The Dining Philosophers
1229. Meeting Scheduler
123. Best Time to Buy and Sell Stock III
1235. Maximum Profit in Job Scheduling
124. Binary Tree Maximum Path Sum
1242. Web Crawler Multithreaded
1249. Minimum Remove to Make Valid Parentheses
1257. Smallest Common Region
126. Word Ladder II
1268. Search Suggestions System
127. Word Ladder
1279. Traffic Light Controlled Intersection
128. Longest Consecutive Sequence
129. Sum Root to Leaf Numbers
13. Roman to Integer
130. Surrounded Regions
131. Palindrome Partitioning
1314. Matrix Block Sum
132. Palindrome Partitioning II
1326. Minimum Number of Taps to Open to Water a Garden
133. Clone Graph
1334. Find the City With the Smallest Number of Neighbors at a Threshold Distance
134. Gas Station
1352. Product of the Last K Numbers
1359. Count All Valid Pickup and Delivery Options
1361. Validate Binary Tree Nodes
138. Copy List with Random Pointer
1382. Balance a Binary Search Tree
1386. Cinema Seat Allocation
139. Word Break
14. Longest Common Prefix
140. Word Break II
1404. Number of Steps to Reduce a Number in Binary Representation to One
1405. Longest Happy String
141. Linked List Cycle
142. Linked List Cycle II
1423. Maximum Points You Can Obtain from Cards
1424. Diagonal Traverse II
1428. Leftmost Column with at Least a One
143. Reorder List
144. Binary Tree Preorder Traversal
1443. Minimum Time to Collect All Apples in a Tree
145. Binary Tree Postorder Traversal
146. LRU Cache
147. Insertion Sort List
1472. Design Browser History
148. Sort List
149. Max Points on a Line
15. 3Sum
151. Reverse Words in a String
1514. Path with Maximum Probability
152. Maximum Product Subarray
1522. Diameter of N‐Ary Tree
153. Find Minimum in Rotated Sorted Array
1539. Kth Missing Positive Number
154. Find Minimum in Rotated Sorted Array II
155. Min Stack
156. Binary Tree Upside Down
157. Read N Characters Given Read4
1570. Dot Product of Two Sparse Vectors
158. Read N Characters Given Read4 II Call multiple times
16. 3Sum Closest
160. Intersection of Two Linked Lists
1604. Alert Using Same Key Card Three or More Times in a One Hour Period
161. One Edit Distance
162. Find Peak Element
1626. Best Team With No Conflicts
163. Missing Ranges
1631. Path With Minimum Effort
164. Maximum Gap
1643. Kth Smallest Instructions
1644. Lowest Common Ancestor of a Binary Tree II
1650. Lowest Common Ancestor of a Binary Tree III
1665. Minimum Initial Energy to Finish Tasks
1674. Minimum Moves to Make Array Complementary
1675. Minimize Deviation in Array
168. Excel Sheet Column Title
1680. Concatenation of Consecutive Binary Numbers
1686. Stone Game VI
1690. Stone Game VII
17. Letter Combinations of a Phone Number
171. Excel Sheet Column Number
1712. Ways to Split Array Into Three Subarrays
1722. Minimize Hamming Distance After Swap Operations
1723. Find Minimum Time to Finish All Jobs
1727. Largest Submatrix With Rearrangements
173. Binary Search Tree Iterator
174. Dungeon Game
1755. Closest Subsequence Sum
1760. Minimum Limit of Balls in a Bag
1762. Buildings With an Ocean View
1775. Equal Sum Arrays With Minimum Number of Operations
1787. Make the XOR of All Segments Equal to Zero
179. Largest Number
1801. Number of Orders in the Backlog
1802. Maximum Value at a Given Index in a Bounded Array
1803. Count Pairs With XOR in a Range
1806. Minimum Number of Operations to Reinitialize a Permutation
1808. Maximize Number of Nice Divisors
1825. Finding MK Average
1838. Frequency of the Most Frequent Element
1839. Longest Substring Of All Vowels in Order
1840. Maximum Building Height
1850. Minimum Adjacent Swaps to Reach the Kth Smallest Number
1856. Maximum Subarray Min Product
186. Reverse Words in a String II
1866. Number of Ways to Rearrange Sticks With K Sticks Visible
1868. Product of Two Run‐Length Encoded Arrays
1871. Jump Game VII
188. Best Time to Buy and Sell Stock IV
1882. Process Tasks Using Servers
1888. Minimum Number of Flips to Make the Binary String Alternating
189. Rotate Array
1891. Cutting Ribbons
19. Remove Nth Node From End of List
1905. Count Sub Islands
191. Number of 1 Bits
1915. Number of Wonderful Substrings
1931. Painting a Grid With Three Different Colors
1937. Maximum Number of Points with Cost
198. House Robber
199. Binary Tree Right Side View
2. Add Two Numbers
20. Valid Parentheses
200. Number of Islands
201. Bitwise AND of Numbers Range
202. Happy Number
203. Remove Linked List Elements
204. Count Primes
205. Isomorphic Strings
206. Reverse Linked List
2060. Check if an Original String Exists Given Two Encoded Strings
207. Course Schedule
208. Implement Trie (Prefix Tree)
209. Minimum Size Subarray Sum
21. Merge Two Sorted Lists
210. Course Schedule II
211. Add and Search Word Data structure design
212. Word Search II
213. House Robber II
2133. Check if Every Row and Column Contains All Numbers
214. Shortest Palindrome
215. Kth Largest Element in an Array
216. Combination Sum III
218. The Skyline Problem
22. Generate Parentheses
221. Maximal Square
222. Count Complete Tree Nodes
223. Rectangle Area
224. Basic Calculator
2246. Longest Path With Different Adjacent Characters
225. Implement Stack using Queues
226. Invert Binary Tree
227. Basic Calculator II
2275. Largest Combination With Bitwise AND Greater Than Zero
2276. Count Integers in Intervals
228. Summary Ranges
23. Merge k Sorted Lists
230. Kth Smallest Element in a BST
232. Implement Queue using Stacks
234. Palindrome Linked List
235. Lowest Common Ancestor of a Binary Search Tree
236. Lowest Common Ancestor of a Binary Tree
237. Delete Node in a Linked List
239. Sliding Window Maximum
24. Swap Nodes in Pairs
240. Search a 2D Matrix II
241. Different Ways to Add Parentheses
242. Valid Anagram
243. Shortest Word Distance
244. Shortest Word Distance II
245. Shortest Word Distance III
246. Strobogrammatic Number
247. Strobogrammatic Number II
248. Strobogrammatic Number III
249. Group Shifted Strings
25. Reverse Nodes in k Group
250. Count Univalue Subtrees
251. Flatten 2D Vector
252. Meeting Rooms
253. Meeting Rooms II
254. Factor Combinations
255. Verify Preorder Sequence in Binary Search Tree
256. Paint House
257. Binary Tree Paths
26. Remove Duplicates from Sorted Array
261. Graph Valid Tree
263. Ugly Number
264. Ugly Number II
265. Paint House II
266. Palindrome Permutation
267. Palindrome Permutation II
269. Alien Dictionary
27. Remove Element
270. Closest Binary Search Tree Value
271. Encode and Decode Strings
272. Closest Binary Search Tree Value II
273. Integer to English Words
274. H Index
275. H Index II
276. Paint Fence
277. Find the Celebrity
278. First Bad Version
279. Perfect Squares
28. Implement strStr()
280. Wiggle Sort
281. Zigzag Iterator
282. Expression Add Operators
283. Move Zeroes
284. Peeking Iterator
285. Inorder Successor in BST
286. Walls and Gates
287. Find the Duplicate Number
288. Unique Word Abbreviation
289. Game of Life
29. Divide Two Integers
293. Flip Game
294. Flip Game II
295. Find Median from Data Stream
296. Best Meeting Point
297. Serialize and Deserialize Binary Tree
298. Binary Tree Longest Consecutive Sequence
299. Bulls and Cows
3. Longest Substring Without Repeating Characters
30. Substring with Concatenation of All Words
300. Longest Increasing Subsequence
301. Remove Invalid Parentheses
302. Smallest Rectangle Enclosing Black Pixels
303. Range Sum Query Immutable
304. Range Sum Query 2D Immutable
305. Number of Islands II
306. Additive Number
307. Range Sum Query Mutable
308. Range Sum Query 2D Mutable
309. Best Time to Buy and Sell Stock with Cooldown
31. Next Permutation
310. Minimum Height Trees
311. Sparse Matrix Multiplication
312. Burst Balloons
313. Super Ugly Number
314. Binary Tree Vertical Order Traversal
315. Count of Smaller Numbers After Self
316. Remove Duplicate Letters
317. Shortest Distance from All Buildings
318. Maximum Product of Word Lengths
32. Longest Valid Parentheses
320. Generalized Abbreviation
321. Create Maximum Number
322. Coin Change
323. Number of Connected Components in an Undirected Graph
324. Wiggle Sort II
325. Maximum Size Subarray Sum Equals k
327. Count of Range Sum
328. Odd Even Linked List
329. Longest Increasing Path in a Matrix
33. Search in Rotated Sorted Array
330. Patching Array
331. Verify Preorder Serialization of a Binary Tree
332. Reconstruct Itinerary
333. Largest BST Subtree
334. Increasing Triplet Subsequence
335. Self Crossing
336. Palindrome Pairs
337. House Robber III
338. Counting Bits
339. Nested List Weight Sum
34. Search for a Range
340. Longest Substring with At Most K Distinct Characters
341. Flatten Nested List Iterator
343. Integer Break
344. Reverse String
345. Reverse Vowels of a String
346. Moving Average from Data Stream
347. Top K Frequent Elements
348. Design Tic Tac Toe
349. Intersection of Two Arrays
35. Search Insert Position
350. Intersection of Two Arrays II
351. Android Unlock Patterns
352. Data Stream as Disjoint Intervals
353. Design Snake Game
354. Russian Doll Envelopes
355. Design Twitter
356. Line Reflection
357. Count Numbers with Unique Digits
358. Rearrange String k Distance Apart
359. Logger Rate Limiter
36. Valid Sudoku
360. Sort Transformed Array
361. Bomb Enemy
362. Design Hit Counter
363. Max Sum of Rectangle No Larger Than K
364. Nested List Weight Sum II
365. Water and Jug Problem
366. Find Leaves of Binary Tree
367. Valid Perfect Square
368. Largest Divisible Subset
369. Plus One Linked List
37. Sudoku Solver
370. Range Addition
371. Sum of Two Integers
372. Super Pow
373. Find K Pairs with Smallest Sums
374. Guess Number Higher or Lower
375. Guess Number Higher or Lower II
376. Wiggle Subsequence
377. Combination Sum IV
378. Kth Smallest Element in a Sorted Matrix
38. Count and Say
380. Insert Delete GetRandom O(1)
381. Insert Delete GetRandom O(1) Duplicates allowed
382. Linked List Random Node
384. Shuffle an Array
385. Mini Parser
388. Longest Absolute File Path
39. Combination Sum
392. Is Subsequence
394. Decode String
395. Longest Substring with At Least K Repeating Characters
398. Random Pick Index
399. Evaluate Division
4. Median of Two Sorted Arrays
40. Combination Sum II
404. Sum of Left Leaves
408. Valid Word Abbreviation
41. First Missing Positive
410. Split Array Largest Sum
413. Arithmetic Slices
416. Partition Equal Subset Sum
419. Battleships in a Board
42. Trapping Rain Water
423. Reconstruct Original Digits from English
426. Convert Binary Search Tree to Sorted Doubly Linked List
427. Construct Quad Tree
428. Serialize and Deserialize N ary Tree
43. Multiply Strings
438. Find All Anagrams in a String
44. Wildcard Matching
449. Serialize and Deserialize BST
45. Jump Game II
450. Delete Node in a BST
451. Sort Characters By Frequency
46. Permutations
460. LFU Cache
465. Optimal Account Balancing
468. Validate IP Address
47. Permutations II
470. Implement Rand10() Using Rand7()
472. Concatenated Words
473. Matchsticks to Square
478. Generate Random Point in a Circle
48. Rotate Image
489. Robot Room Cleaner
49. Group Anagrams
490. The Maze
493. Reverse Pairs
494. Target Sum
498. Diagonal Traverse
499. The Maze III
5. Longest Palindromic Substring
50. Pow(x, n)
505. The Maze II
51. N Queens
518. Coin Change 2
52. N Queens II
523. Continuous Subarray Sum
528. Random Pick with Weight
529. Minesweeper
53. Maximum Subarray
532. K diff Pairs in an Array
536. Construct Binary Tree from String
54. Spiral Matrix
542. 01 Matrix
543. Diameter of Binary Tree
56. Merge Intervals
560. Subarray Sum Equals K
568. Maximum Vacation Days
57. Insert Interval
572. Subtree of Another Tree
588. Design In Memory File System
59. Spiral Matrix II
60. Permutation Sequence
609. Find Duplicate File in System
61. Rotate List
62. Unique Paths
621. Task Scheduler
63. Unique Paths II
631. Design Excel Sum Formula
636. Exclusive Time of Functions
64. Minimum Path Sum
642. Design Search Autocomplete System
646. Maximum Length of Pair Chain
65. Valid Number
67. Add Binary
670. Maximum Swap
675. Cut Off Trees for Golf Event
68. Text Justification
680. Valid Palindrome II
688. Knight Probability in Chessboard
69. Sqrt(x)
691. Stickers to Spell Word
692. Top K Frequent Words
694. Number of Distinct Islands
698. Partition to K Equal Sum Subsets
70. Climbing Stairs
708. Insert into a Sorted Circular Linked List
71. Simplify Path
712. Minimum ASCII Delete Sum for Two Strings
714. Best Time to Buy and Sell Stock with Transaction Fee
718. Maximum Length of Repeated Subarray
72. Edit Distance
721. Accounts Merge
73. Set Matrix Zeroes
731. My Calendar II
732. My Calendar III
733. Flood Fill
735. Asteroid Collision
739. Daily Temperatures
74. Search a 2D Matrix
743. Network Delay Time
75. Sort Colors
750. Number Of Corner Rectangles
751. IP to CIDR
755. Pour Water
759. Employee Free Time
76. Minimum Window Substring
766. Toeplitz Matrix
767. Reorganize String
77. Combinations
772. Basic Calculator III
777. Swap Adjacent in LR String
78. Subsets
785. Is Graph Bipartite?
787. Cheapest Flights Within K Stops
79. Word Search
791. Custom Sort String
797. All Paths From Source to Target
8. String to Integer (atoi)
81. Search in Rotated Sorted Array II
815. Bus Routes
82. Remove Duplicates from Sorted List II
827. Making A Large Island
829. Consecutive Numbers Sum
83. Remove Duplicates from Sorted List
839. Similar String Groups
84. Largest Rectangle in Histogram
843. Guess the Word
847. Shortest Path Visiting All Nodes
85. Maximal Rectangle
854. K Similar Strings
86. Partition List
863. All Nodes Distance K in Binary Tree
864. Shortest Path to Get All Keys
87. Scramble String
872. Leaf‐Similar Trees
877. Stone Game
88. Merge Sorted Array
885. Spiral Matrix III
886. Possible Bipartition
895. Maximum Frequency Stack
90. Subsets II
907. Sum of Subarray Minimums
91. Decode Ways
917. Reverse Only Letters
92. Reverse Linked List II
921. Minimum Add to Make Parentheses Valid
923. 3Sum With Multiplicity
93. Restore IP Addresses
938. Range Sum of BST
94. Binary Tree Inorder Traversal
945. Minimum Increment to Make Array Unique
95. Unique Binary Search Trees II
953. Verifying an Alien Dictionary
958. Check Completeness of a Binary Tree
959. Regions Cut By Slashes
96. Unique Binary Search Trees
97. Interleaving String
973. K Closest Points to Origin
98. Validate Binary Search Tree
981. Time Based Key Value Store
986. Interval List Intersections
987. Vertical Order Traversal of a Binary Tree
99. Recover Binary Search Tree
Array & string
BFS Shortest Path Template
Binary Index Tree
Binary search
Binary search (bug)
Bit wise
Bitwise operation
Concurrency
Cycle detection in directed graph
Data Structure: Binary Index Tree
Data Structure: Union Find
Design
DFS & BFS
Divide and Conquer
Dynamic programming
English
Find out repeated number in array
Graph
Greedy
Heuristic
Josephus problem (count out)
LC 319: Bulb Switcher
Line Sweep
Linked list
Logical and Maintainable
Math
merge sort
Preface
Python Notes
quick sort
Random and Sampling
Sort
Stack and Queue
Terms
tree
TreeMap
Trie
Two pointers
Union find

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