1

Two Sum

Easy

2

Add Two Numbers

Medium

3

Longest Substring Without Repeating Characters

Medium

4

Median of Two Sorted Arrays

Hard

5

Longest Palindromic Substring

Medium

6

ZigZag Conversion

Medium

7

Reverse Integer

Easy

8

String to Integer (atoi)

Medium

9

Palindrome Number

Easy

10

Regular Expression Matching

Hard

11

Container With Most Water

Medium

12

Integer to Roman

Medium

13

Roman to Integer

Easy

14

Longest Common Prefix

Easy

15

3Sum

Medium

16

3Sum Closest

Medium

17

Letter Combinations of a Phone Number

Medium

18

4Sum

Medium

19

Remove Nth Node From End of List

Medium

20

Valid Parentheses

Easy

21

Merge Two Sorted Lists

Easy

22

Generate Parentheses

Medium

23

Merge k Sorted Lists

Hard

24

Swap Nodes in Pairs

Medium

25

Reverse Nodes in kGroup

Hard

26

Remove Duplicates from Sorted Array

Easy

27

Remove Element

Easy

28

Implement strStr()

Easy

29

Divide Two Integers

Medium

30

Substring with Concatenation of All Words

Hard

31

Next Permutation

Medium

32

Longest Valid Parentheses

Hard

33

Search in Rotated Sorted Array

Medium

34

Find First and Last Position of Element in Sorted Array

Medium

35

Search Insert Position

Easy

36

Valid Sudoku

Medium

37

Sudoku Solver

Hard

38

Count and Say

Medium

39

Combination Sum

Medium

40

Combination Sum II

Medium

41

First Missing Positive

Hard

42

Trapping Rain Water

Hard

43

Multiply Strings

Medium

44

Wildcard Matching

Hard

45

Jump Game II

Medium

46

Permutations

Medium

47

Permutations II

Medium

48

Rotate Image

Medium

49

Group Anagrams

Medium

50

Pow(x, n)

Medium

51

NQueens

Hard

52

NQueens II

Hard

53

Maximum Subarray

Easy

54

Spiral Matrix

Medium

55

Jump Game

Medium

56

Merge Intervals

Medium

57

Insert Interval

Medium

58

Length of Last Word

Easy

59

Spiral Matrix II

Medium

60

Permutation Sequence

Hard

61

Rotate List

Medium

62

Unique Paths

Medium

63

Unique Paths II

Medium

64

Minimum Path Sum

Medium

65

Valid Number

Hard

66

Plus One

Easy

67

Add Binary

Easy

68

Text Justification

Hard

69

Sqrt(x)

Easy

70

Climbing Stairs

Easy

71

Simplify Path

Medium

72

Edit Distance

Hard

73

Set Matrix Zeroes

Medium

74

Search a 2D Matrix

Medium

75

Sort Colors

Medium

76

Minimum Window Substring

Hard

77

Combinations

Medium

78

Subsets

Medium

79

Word Search

Medium

80

Remove Duplicates from Sorted Array II

Medium

81

Search in Rotated Sorted Array II

Medium

82

Remove Duplicates from Sorted List II

Medium

83

Remove Duplicates from Sorted List

Easy

84

Largest Rectangle in Histogram

Hard

85

Maximal Rectangle

Hard

86

Partition List

Medium

87

Scramble String

Hard

88

Merge Sorted Array

Easy

89

Gray Code

Medium

90

Subsets II

Medium

91

Decode Ways

Medium

92

Reverse Linked List II

Medium

93

Restore IP Addresses

Medium

94

Binary Tree Inorder Traversal

Easy

95

Unique Binary Search Trees II

Medium

96

Unique Binary Search Trees

Medium

97

Interleaving String

Medium

98

Validate Binary Search Tree

Medium

99

Recover Binary Search Tree

Medium

100

Same Tree

Easy

101

Symmetric Tree

Easy

102

Binary Tree Level Order Traversal

Medium

103

Binary Tree Zigzag Level Order Traversal

Medium

104

Maximum Depth of Binary Tree

Easy

105

Construct Binary Tree from Preorder and Inorder Traversal

Medium

106

Construct Binary Tree from Inorder and Postorder Traversal

Medium

107

Binary Tree Level Order Traversal II

Medium

108

Convert Sorted Array to Binary Search Tree

Easy

109

Convert Sorted List to Binary Search Tree

Medium

110

Balanced Binary Tree

Easy

111

Minimum Depth of Binary Tree

Easy

112

Path Sum

Easy

113

Path Sum II

Medium

114

Flatten Binary Tree to Linked List

Medium

115

Distinct Subsequences

Hard

118

Pascal's Triangle

Easy

120

Triangle

Medium

121

Best Time to Buy and Sell Stock

Easy

122

Best Time to Buy and Sell Stock II

Easy

123

Best Time to Buy and Sell Stock III

Hard

124

Binary Tree Maximum Path Sum

Hard

125

Valid Palindrome

Easy

126

Word Ladder II

Hard

127

Word Ladder

Hard

128

Longest Consecutive Sequence

Medium

129

Sum Root to Leaf Numbers

Medium

130

Surrounded Regions

Medium

131

Palindrome Partitioning

Medium

132

Palindrome Partitioning II

Hard

134

Gas Station

Medium

135

Candy

Hard

136

Single Number

Easy

137

Single Number II

Medium

139

Word Break

Medium

140

Word Break II

Hard

143

Reorder List

Medium

144

Binary Tree Preorder Traversal

Easy

145

Binary Tree Postorder Traversal

Easy

146

LRU Cache

Medium

147

Insertion Sort List

Medium

148

Sort List

Medium

149

Max Points on a Line

Hard

150

Evaluate Reverse Polish Notation

Medium

151

Reverse Words in a String

Medium

152

Maximum Product Subarray

Medium

153

Find Minimum in Rotated Sorted Array

Medium

154

Find Minimum in Rotated Sorted Array II

Hard

155

Min Stack

Easy

156

Binary Tree Upside Down

Medium

157

Read N Characters Given Read4

Easy

159

Longest Substring with At Most Two Distinct Characters

Medium

161

One Edit Distance

Medium

162

Find Peak Element

Medium

163

Missing Ranges

Easy

164

Maximum Gap

Hard

165

Compare Version Numbers

Medium

166

Fraction to Recurring Decimal

Medium

167

Two Sum II  Input array is sorted

Easy

168

Excel Sheet Column Title

Easy

169

Majority Element

Easy

170

Two Sum III  Data structure design

Easy

171

Excel Sheet Column Number

Easy

172

Factorial Trailing Zeroes

Easy

173

Binary Search Tree Iterator

Medium

174

Dungeon Game

Hard

179

Largest Number

Medium

186

Reverse Words in a String II

Medium

187

Repeated DNA Sequences

Medium

188

Best Time to Buy and Sell Stock IV

Hard

189

Rotate Array

Medium

190

Reverse Bits

Easy

191

Number of 1 Bits

Easy

198

House Robber

Medium

199

Binary Tree Right Side View

Medium

200

Number of Islands

Medium

201

Bitwise AND of Numbers Range

Medium

202

Happy Number

Easy

203

Remove Linked List Elements

Easy

204

Count Primes

Easy

205

Isomorphic Strings

Easy

206

Reverse Linked List

Easy

207

Course Schedule

Medium

208

Implement Trie (Prefix Tree)

Medium

209

Minimum Size Subarray Sum

Medium

210

Course Schedule II

Medium

211

Design Add and Search Words Data Structure

Medium

212

Word Search II

Hard

213

House Robber II

Medium

214

Shortest Palindrome

Hard

215

Kth Largest Element in an Array

Medium

216

Combination Sum III

Medium

217

Contains Duplicate

Easy

218

The Skyline Problem

Hard

219

Contains Duplicate II

Easy

220

Contains Duplicate III

Medium

221

Maximal Square

Medium

222

Count Complete Tree Nodes

Medium

223

Rectangle Area

Medium

224

Basic Calculator

Hard

225

Implement Stack using Queues

Easy

226

Invert Binary Tree

Easy

227

Basic Calculator II

Medium

228

Summary Ranges

Easy

229

Majority Element II

Medium

230

Kth Smallest Element in a BST

Medium

231

Power of Two

Easy

232

Implement Queue using Stacks

Easy

233

Number of Digit One

Hard

234

Palindrome Linked List

Easy

235

Lowest Common Ancestor of a Binary Search Tree

Easy

236

Lowest Common Ancestor of a Binary Tree

Medium

238

Product of Array Except Self

Medium

239

Sliding Window Maximum

Hard

240

Search a 2D Matrix II

Medium

241

Different Ways to Add Parentheses

Medium

242

Valid Anagram

Easy

243

Shortest Word Distance

Easy

244

Shortest Word Distance II

Medium

245

Shortest Word Distance III

Medium

246

Strobogrammatic Number

Easy

247

Strobogrammatic Number II

Medium

248

Strobogrammatic Number III

Hard

249

Group Shifted Strings

Medium

250

Count Univalue Subtrees

Medium

251

Flatten 2D Vector

Medium

252

Meeting Rooms

Easy

253

Meeting Rooms II

Medium

254

Factor Combinations

Medium

255

Verify Preorder Sequence in Binary Search Tree

Medium

256

Paint House

Medium

257

Binary Tree Paths

Easy

258

Add Digits

Easy

259

3Sum Smaller

Medium

260

Single Number III

Medium

261

Graph Valid Tree

Medium

263

Ugly Number

Easy

264

Ugly Number II

Medium

265

Paint House II

Hard

266

Palindrome Permutation

Easy

267

Palindrome Permutation II

Medium

268

Missing Number

Easy

269

Alien Dictionary

Hard

270

Closest Binary Search Tree Value

Easy

271

Encode and Decode Strings

Medium

272

Closest Binary Search Tree Value II

Hard

273

Integer to English Words

Hard

274

HIndex

Medium

275

HIndex II

Medium

276

Paint Fence

Medium

277

Find the Celebrity

Medium

278

First Bad Version

Easy

279

Perfect Squares

Medium

280

Wiggle Sort

Medium

281

Zigzag Iterator

Medium

282

Expression Add Operators

Hard

283

Move Zeroes

Easy

285

Inorder Successor in BST

Medium

286

Walls and Gates

Medium

287

Find the Duplicate Number

Medium

288

Unique Word Abbreviation

Medium

289

Game of Life

Medium

290

Word Pattern

Easy

291

Word Pattern II

Medium

292

Nim Game

Easy

293

Flip Game

Easy

294

Flip Game II

Medium

295

Find Median from Data Stream

Hard

296

Best Meeting Point

Hard

297

Serialize and Deserialize Binary Tree

Hard

298

Binary Tree Longest Consecutive Sequence

Medium

299

Bulls and Cows

Medium

300

Longest Increasing Subsequence

Medium

301

Remove Invalid Parentheses

Hard

302

Smallest Rectangle Enclosing Black Pixels

Hard

303

Range Sum Query  Immutable

Easy

304

Range Sum Query 2D  Immutable

Medium

305

Number of Islands II

Hard

306

Additive Number

Medium

307

Range Sum Query  Mutable

Medium

309

Best Time to Buy and Sell Stock with Cooldown

Medium

310

Minimum Height Trees

Medium

311

Sparse Matrix Multiplication

Medium

312

Burst Balloons

Hard

313

Super Ugly Number

Medium

314

Binary Tree Vertical Order Traversal

Medium

315

Count of Smaller Numbers After Self

Hard

316

Remove Duplicate Letters

Medium

317

Shortest Distance from All Buildings

Hard

318

Maximum Product of Word Lengths

Medium

319

Bulb Switcher

Medium

320

Generalized Abbreviation

Medium

321

Create Maximum Number

Hard

322

Coin Change

Medium

323

Number of Connected Components in an Undirected Graph

Medium

324

Wiggle Sort II

Medium

325

Maximum Size Subarray Sum Equals k

Medium

326

Power of Three

Easy

328

Odd Even Linked List

Medium

329

Longest Increasing Path in a Matrix

Hard

330

Patching Array

Hard

331

Verify Preorder Serialization of a Binary Tree

Medium

332

Reconstruct Itinerary

Medium

333

Largest BST Subtree

Medium

334

Increasing Triplet Subsequence

Medium

336

Palindrome Pairs

Hard

337

House Robber III

Medium

338

Counting Bits

Easy

339

Nested List Weight Sum

Medium

340

Longest Substring with At Most K Distinct Characters

Medium

341

Flatten Nested List Iterator

Medium

342

Power of Four

Easy

343

Integer Break

Medium

344

Reverse String

Easy

345

Reverse Vowels of a String

Easy

346

Moving Average from Data Stream

Easy

347

Top K Frequent Elements

Medium

348

Design TicTacToe

Medium

349

Intersection of Two Arrays

Easy

350

Intersection of Two Arrays II

Easy

351

Android Unlock Patterns

Medium

352

Data Stream as Disjoint Intervals

Hard

353

Design Snake Game

Medium

354

Russian Doll Envelopes

Hard

355

Design Twitter

Medium

356

Line Reflection

Medium

357

Count Numbers with Unique Digits

Medium

358

Rearrange String k Distance Apart

Hard

359

Logger Rate Limiter

Easy

360

Sort Transformed Array

Medium

361

Bomb Enemy

Medium

362

Design Hit Counter

Medium

363

Max Sum of Rectangle No Larger Than K

Hard

364

Nested List Weight Sum II

Medium

365

Water and Jug Problem

Medium

366

Find Leaves of Binary Tree

Medium

367

Valid Perfect Square

Easy

368

Largest Divisible Subset

Medium

369

Plus One Linked List

Medium

370

Range Addition

Medium

371

Sum of Two Integers

Medium

372

Super Pow

Medium

373

Find K Pairs with Smallest Sums

Medium

374

Guess Number Higher or Lower

Easy

375

Guess Number Higher or Lower II

Medium

376

Wiggle Subsequence

Medium

377

Combination Sum IV

Medium

378

Kth Smallest Element in a Sorted Matrix

Medium

379

Design Phone Directory

Medium

380

Insert Delete GetRandom O(1)

Medium

381

Insert Delete GetRandom O(1)  Duplicates allowed

Hard

382

Linked List Random Node

Medium

383

Ransom Note

Easy

384

Shuffle an Array

Medium

385

Mini Parser

Medium

386

Lexicographical Numbers

Medium

387

First Unique Character in a String

Easy

388

Longest Absolute File Path

Medium

389

Find the Difference

Easy

390

Elimination Game

Medium

391

Perfect Rectangle

Hard

392

Is Subsequence

Easy

393

UTF8 Validation

Medium

394

Decode String

Medium

395

Longest Substring with At Least K Repeating Characters

Medium

396

Rotate Function

Medium

397

Integer Replacement

Medium

398

Random Pick Index

Medium

399

Evaluate Division

Medium

400

Nth Digit

Medium

401

Binary Watch

Easy

402

Remove K Digits

Medium

403

Frog Jump

Hard

404

Sum of Left Leaves

Easy

405

Convert a Number to Hexadecimal

Easy

406

Queue Reconstruction by Height

Medium

407

Trapping Rain Water II

Hard

408

Valid Word Abbreviation

Easy

409

Longest Palindrome

Easy

410

Split Array Largest Sum

Hard

411

Minimum Unique Word Abbreviation

Hard

412

Fizz Buzz

Easy

413

Arithmetic Slices

Medium

414

Third Maximum Number

Easy

415

Add Strings

Easy

416

Partition Equal Subset Sum

Medium

417

Pacific Atlantic Water Flow

Medium

418

Sentence Screen Fitting

Medium

419

Battleships in a Board

Medium

420

Strong Password Checker

Hard

421

Maximum XOR of Two Numbers in an Array

Medium

422

Valid Word Square

Easy

423

Reconstruct Original Digits from English

Medium

424

Longest Repeating Character Replacement

Medium

425

Word Squares

Hard

432

All O`one Data Structure

Hard

433

Minimum Genetic Mutation

Medium

434

Number of Segments in a String

Easy

435

Nonoverlapping Intervals

Medium

436

Find Right Interval

Medium

437

Path Sum III

Medium

438

Find All Anagrams in a String

Medium

439

Ternary Expression Parser

Medium

440

Kth Smallest in Lexicographical Order

Hard

441

Arranging Coins

Easy

442

Find All Duplicates in an Array

Medium

443

String Compression

Medium

444

Sequence Reconstruction

Medium

445

Add Two Numbers II

Medium

446

Arithmetic Slices II  Subsequence

Hard

447

Number of Boomerangs

Medium

448

Find All Numbers Disappeared in an Array

Easy

449

Serialize and Deserialize BST

Medium

450

Delete Node in a BST

Medium

451

Sort Characters By Frequency

Medium

452

Minimum Number of Arrows to Burst Balloons

Medium

453

Minimum Moves to Equal Array Elements

Easy

454

4Sum II

Medium

455

Assign Cookies

Easy

456

132 Pattern

Medium

457

Circular Array Loop

Medium

458

Poor Pigs

Hard

459

Repeated Substring Pattern

Easy

460

LFU Cache

Hard

461

Hamming Distance

Easy

462

Minimum Moves to Equal Array Elements II

Medium

463

Island Perimeter

Easy

464

Can I Win

Medium

465

Optimal Account Balancing

Hard

467

Unique Substrings in Wraparound String

Medium

468

Validate IP Address

Medium

469

Convex Polygon

Medium

470

Implement Rand10() Using Rand7()

Medium

471

Encode String with Shortest Length

Hard

472

Concatenated Words

Hard

473

Matchsticks to Square

Medium

474

Ones and Zeroes

Medium

475

Heaters

Medium

476

Number Complement

Easy

477

Total Hamming Distance

Medium

478

Generate Random Point in a Circle

Medium

479

Largest Palindrome Product

Hard

480

Sliding Window Median

Hard

481

Magical String

Medium

482

License Key Formatting

Easy

484

Find Permutation

Medium

485

Max Consecutive Ones

Easy

486

Predict the Winner

Medium

487

Max Consecutive Ones II

Medium

488

Zuma Game

Hard

490

The Maze

Medium

491

Increasing Subsequences

Medium

492

Construct the Rectangle

Easy

493

Reverse Pairs

Hard

494

Target Sum

Medium

495

Teemo Attacking

Easy

496

Next Greater Element I

Easy

497

Random Point in Nonoverlapping Rectangles

Medium

498

Diagonal Traverse

Medium

499

The Maze III

Hard

500

Keyboard Row

Easy

501

Find Mode in Binary Search Tree

Easy

502

IPO

Hard

503

Next Greater Element II

Medium

504

Base 7

Easy

505

The Maze II

Medium

506

Relative Ranks

Easy

507

Perfect Number

Easy

508

Most Frequent Subtree Sum

Medium

509

Fibonacci Number

Easy

513

Find Bottom Left Tree Value

Medium

514

Freedom Trail

Hard

515

Find Largest Value in Each Tree Row

Medium

516

Longest Palindromic Subsequence

Medium

517

Super Washing Machines

Hard

518

Coin Change 2

Medium

519

Random Flip Matrix

Medium

520

Detect Capital

Easy

521

Longest Uncommon Subsequence I

Easy

522

Longest Uncommon Subsequence II

Medium

523

Continuous Subarray Sum

Medium

524

Longest Word in Dictionary through Deleting

Medium

525

Contiguous Array

Medium

526

Beautiful Arrangement

Medium

527

Word Abbreviation

Hard

528

Random Pick with Weight

Medium

529

Minesweeper

Medium

530

Minimum Absolute Difference in BST

Easy

531

Lonely Pixel I

Medium

532

Kdiff Pairs in an Array

Medium

533

Lonely Pixel II

Medium

535

Encode and Decode TinyURL

Medium

536

Construct Binary Tree from String

Medium

537

Complex Number Multiplication

Medium

538

Convert BST to Greater Tree

Medium

539

Minimum Time Difference

Medium

540

Single Element in a Sorted Array

Medium

541

Reverse String II

Easy

542

01 Matrix

Medium

543

Diameter of Binary Tree

Easy

544

Output Contest Matches

Medium

545

Boundary of Binary Tree

Medium

546

Remove Boxes

Hard

547

Number of Provinces

Medium

548

Split Array with Equal Sum

Medium

549

Binary Tree Longest Consecutive Sequence II

Medium

551

Student Attendance Record I

Easy

552

Student Attendance Record II

Hard

553

Optimal Division

Medium

554

Brick Wall

Medium

555

Split Concatenated Strings

Medium

556

Next Greater Element III

Medium

557

Reverse Words in a String III

Easy

560

Subarray Sum Equals K

Medium

561

Array Partition I

Easy

562

Longest Line of Consecutive One in Matrix

Medium

563

Binary Tree Tilt

Easy

564

Find the Closest Palindrome

Hard

565

Array Nesting

Medium

566

Reshape the Matrix

Easy

567

Permutation in String

Medium

568

Maximum Vacation Days

Hard

572

Subtree of Another Tree

Easy

573

Squirrel Simulation

Medium

575

Distribute Candies

Easy

576

Out of Boundary Paths

Medium

581

Shortest Unsorted Continuous Subarray

Medium

582

Kill Process

Medium

583

Delete Operation for Two Strings

Medium

588

Design InMemory File System

Hard

591

Tag Validator

Hard

592

Fraction Addition and Subtraction

Medium

593

Valid Square

Medium

594

Longest Harmonious Subsequence

Easy

598

Range Addition II

Easy

599

Minimum Index Sum of Two Lists

Easy

604

Design Compressed String Iterator

Easy

605

Can Place Flowers

Easy

606

Construct String from Binary Tree

Easy

609

Find Duplicate File in System

Medium

611

Valid Triangle Number

Medium

616

Add Bold Tag in String

Medium

617

Merge Two Binary Trees

Easy

621

Task Scheduler

Medium

622

Design Circular Queue

Medium

623

Add One Row to Tree

Medium

624

Maximum Distance in Arrays

Medium

625

Minimum Factorization

Medium

628

Maximum Product of Three Numbers

Easy

630

Course Schedule III

Hard

631

Design Excel Sum Formula

Hard

632

Smallest Range Covering Elements from K Lists

Hard

633

Sum of Square Numbers

Medium

634

Find the Derangement of An Array

Medium

635

Design Log Storage System

Medium

636

Exclusive Time of Functions

Medium

637

Average of Levels in Binary Tree

Easy

638

Shopping Offers

Medium

640

Solve the Equation

Medium

641

Design Circular Deque

Medium

642

Design Search Autocomplete System

Hard

643

Maximum Average Subarray I

Easy

645

Set Mismatch

Easy

646

Maximum Length of Pair Chain

Medium

647

Palindromic Substrings

Medium

648

Replace Words

Medium

649

Dota2 Senate

Medium

650

2 Keys Keyboard

Medium

651

4 Keys Keyboard

Medium

652

Find Duplicate Subtrees

Medium

653

Two Sum IV  Input is a BST

Easy

654

Maximum Binary Tree

Medium

655

Print Binary Tree

Medium

657

Robot Return to Origin

Easy

658

Find K Closest Elements

Medium

659

Split Array into Consecutive Subsequences

Medium

660

Remove 9

Hard

661

Image Smoother

Easy

662

Maximum Width of Binary Tree

Medium

663

Equal Tree Partition

Medium

665

Nondecreasing Array

Medium

666

Path Sum IV

Medium

667

Beautiful Arrangement II

Medium

668

Kth Smallest Number in Multiplication Table

Hard

669

Trim a Binary Search Tree

Medium

670

Maximum Swap

Medium

671

Second Minimum Node In a Binary Tree

Easy

672

Bulb Switcher II

Medium

673

Number of Longest Increasing Subsequence

Medium

674

Longest Continuous Increasing Subsequence

Easy

675

Cut Off Trees for Golf Event

Hard

676

Implement Magic Dictionary

Medium

677

Map Sum Pairs

Medium

678

Valid Parenthesis String

Medium

679

24 Game

Hard

680

Valid Palindrome II

Easy

681

Next Closest Time

Medium

682

Baseball Game

Easy

683

K Empty Slots

Hard

684

Redundant Connection

Medium

686

Repeated String Match

Medium

687

Longest Univalue Path

Medium

688

Knight Probability in Chessboard

Medium

689

Maximum Sum of 3 NonOverlapping Subarrays

Hard

692

Top K Frequent Words

Medium

693

Binary Number with Alternating Bits

Easy

694

Number of Distinct Islands

Medium

695

Max Area of Island

Medium

696

Count Binary Substrings

Easy

697

Degree of an Array

Easy

698

Partition to K Equal Sum Subsets

Medium

700

Search in a Binary Search Tree

Easy

701

Insert into a Binary Search Tree

Medium

703

Kth Largest Element in a Stream

Easy

704

Binary Search

Easy

705

Design HashSet

Easy

706

Design HashMap

Easy

707

Design Linked List

Medium

709

To Lower Case

Easy

710

Random Pick with Blacklist

Hard

712

Minimum ASCII Delete Sum for Two Strings

Medium

713

Subarray Product Less Than K

Medium

714

Best Time to Buy and Sell Stock with Transaction Fee

Medium

716

Max Stack

Easy

717

1bit and 2bit Characters

Easy

718

Maximum Length of Repeated Subarray

Medium

719

Find Kth Smallest Pair Distance

Hard

720

Longest Word in Dictionary

Medium

721

Accounts Merge

Medium

722

Remove Comments

Medium

723

Candy Crush

Medium

724

Find Pivot Index

Easy

725

Split Linked List in Parts

Medium

726

Number of Atoms

Hard

727

Minimum Window Subsequence

Hard

728

Self Dividing Numbers

Easy

729

My Calendar I

Medium

731

My Calendar II

Medium

732

My Calendar III

Hard

733

Flood Fill

Easy

734

Sentence Similarity

Easy

735

Asteroid Collision

Medium

736

Parse Lisp Expression

Hard

737

Sentence Similarity II

Medium

738

Monotone Increasing Digits

Medium

739

Daily Temperatures

Medium

740

Delete and Earn

Medium

742

Closest Leaf in a Binary Tree

Medium

743

Network Delay Time

Medium

744

Find Smallest Letter Greater Than Target

Easy

746

Min Cost Climbing Stairs

Easy

747

Largest Number At Least Twice of Others

Easy

748

Shortest Completing Word

Easy

750

Number Of Corner Rectangles

Medium

751

IP to CIDR

Medium

752

Open the Lock

Medium

753

Cracking the Safe

Hard

754

Reach a Number

Medium

755

Pour Water

Medium

756

Pyramid Transition Matrix

Medium

758

Bold Words in String

Medium

759

Employee Free Time

Hard

760

Find Anagram Mappings

Easy

761

Special Binary String

Hard

762

Prime Number of Set Bits in Binary Representation

Easy

763

Partition Labels

Medium

764

Largest Plus Sign

Medium

765

Couples Holding Hands

Hard

766

Toeplitz Matrix

Easy

767

Reorganize String

Medium

768

Max Chunks To Make Sorted II

Hard

769

Max Chunks To Make Sorted

Medium

770

Basic Calculator IV

Hard

771

Jewels and Stones

Easy

772

Basic Calculator III

Hard

773

Sliding Puzzle

Hard

774

Minimize Max Distance to Gas Station

Hard

775

Global and Local Inversions

Medium

776

Split BST

Medium

777

Swap Adjacent in LR String

Medium

778

Swim in Rising Water

Hard

779

Kth Symbol in Grammar

Medium

780

Reaching Points

Hard

781

Rabbits in Forest

Medium

783

Minimum Distance Between BST Nodes

Easy

784

Letter Case Permutation

Medium

785

Is Graph Bipartite?

Medium

786

Kth Smallest Prime Fraction

Hard

787

Cheapest Flights Within K Stops

Medium

788

Rotated Digits

Medium

789

Escape The Ghosts

Medium

790

Domino and Tromino Tiling

Medium

791

Custom Sort String

Medium

792

Number of Matching Subsequences

Medium

794

Valid TicTacToe State

Medium

795

Number of Subarrays with Bounded Maximum

Medium

796

Rotate String

Easy

797

All Paths From Source to Target

Medium

799

Champagne Tower

Medium

800

Similar RGB Color

Easy

801

Minimum Swaps To Make Sequences Increasing

Hard

802

Find Eventual Safe States

Medium

804

Unique Morse Code Words

Easy

805

Split Array With Same Average

Hard

806

Number of Lines To Write String

Easy

807

Max Increase to Keep City Skyline

Medium

808

Soup Servings

Medium

809

Expressive Words

Medium

810

Chalkboard XOR Game

Hard

811

Subdomain Visit Count

Easy

812

Largest Triangle Area

Easy

813

Largest Sum of Averages

Medium

814

Binary Tree Pruning

Medium

815

Bus Routes

Hard

816

Ambiguous Coordinates

Medium

817

Linked List Components

Medium

818

Race Car

Hard

819

Most Common Word

Easy

820

Short Encoding of Words

Medium

821

Shortest Distance to a Character

Easy

822

Card Flipping Game

Medium

823

Binary Trees With Factors

Medium

824

Goat Latin

Easy

825

Friends Of Appropriate Ages

Medium

826

Most Profit Assigning Work

Medium

827

Making A Large Island

Hard

828

Count Unique Characters of All Substrings of a Given String

Hard

829

Consecutive Numbers Sum

Hard

830

Positions of Large Groups

Easy

831

Masking Personal Information

Medium

832

Flipping an Image

Easy

833

Find And Replace in String

Medium

835

Image Overlap

Medium

836

Rectangle Overlap

Easy

837

New 21 Game

Medium

838

Push Dominoes

Medium

840

Magic Squares In Grid

Medium

841

Keys and Rooms

Medium

842

Split Array into Fibonacci Sequence

Medium

843

Guess the Word

Hard

844

Backspace String Compare

Easy

845

Longest Mountain in Array

Medium

846

Hand of Straights

Medium

847

Shortest Path Visiting All Nodes

Hard

848

Shifting Letters

Medium

849

Maximize Distance to Closest Person

Medium

851

Loud and Rich

Medium

852

Peak Index in a Mountain Array

Easy

853

Car Fleet

Medium

854

KSimilar Strings

Hard

855

Exam Room

Medium

856

Score of Parentheses

Medium

857

Minimum Cost to Hire K Workers

Hard

858

Mirror Reflection

Medium

859

Buddy Strings

Easy

860

Lemonade Change

Easy

861

Score After Flipping Matrix

Medium

862

Shortest Subarray with Sum at Least K

Hard

863

All Nodes Distance K in Binary Tree

Medium

865

Smallest Subtree with all the Deepest Nodes

Medium

866

Prime Palindrome

Medium

867

Transpose Matrix

Easy

868

Binary Gap

Easy

869

Reordered Power of 2

Medium

870

Advantage Shuffle

Medium

871

Minimum Number of Refueling Stops

Hard

872

LeafSimilar Trees

Easy

873

Length of Longest Fibonacci Subsequence

Medium

874

Walking Robot Simulation

Easy

875

Koko Eating Bananas

Medium

876

Middle of the Linked List

Easy

877

Stone Game

Medium

880

Decoded String at Index

Medium

881

Boats to Save People

Medium

883

Projection Area of 3D Shapes

Easy

884

Uncommon Words from Two Sentences

Easy

885

Spiral Matrix III

Medium

886

Possible Bipartition

Medium

888

Fair Candy Swap

Easy

889

Construct Binary Tree from Preorder and Postorder Traversal

Medium

890

Find and Replace Pattern

Medium

891

Sum of Subsequence Widths

Hard

892

Surface Area of 3D Shapes

Easy

893

Groups of SpecialEquivalent Strings

Easy

894

All Possible Full Binary Trees

Medium

895

Maximum Frequency Stack

Hard

896

Monotonic Array

Easy

897

Increasing Order Search Tree

Easy

898

Bitwise ORs of Subarrays

Medium

899

Orderly Queue

Hard

900

RLE Iterator

Medium

901

Online Stock Span

Medium

903

Valid Permutations for DI Sequence

Hard

904

Fruit Into Baskets

Medium

905

Sort Array By Parity

Easy

907

Sum of Subarray Minimums

Medium

908

Smallest Range I

Easy

909

Snakes and Ladders

Medium

910

Smallest Range II

Medium

911

Online Election

Medium

912

Sort an Array

Medium

914

X of a Kind in a Deck of Cards

Easy

915

Partition Array into Disjoint Intervals

Medium

916

Word Subsets

Medium

917

Reverse Only Letters

Easy

918

Maximum Sum Circular Subarray

Medium

919

Complete Binary Tree Inserter

Medium

921

Minimum Add to Make Parentheses Valid

Medium

922

Sort Array By Parity II

Easy

923

3Sum With Multiplicity

Medium

924

Minimize Malware Spread

Hard

925

Long Pressed Name

Easy

926

Flip String to Monotone Increasing

Medium

929

Unique Email Addresses

Easy

930

Binary Subarrays With Sum

Medium

931

Minimum Falling Path Sum

Medium

932

Beautiful Array

Medium

933

Number of Recent Calls

Easy

934

Shortest Bridge

Medium

935

Knight Dialer

Medium

937

Reorder Data in Log Files

Easy

938

Range Sum of BST

Easy

939

Minimum Area Rectangle

Medium

941

Valid Mountain Array

Easy

942

DI String Match

Easy

944

Delete Columns to Make Sorted

Easy

945

Minimum Increment to Make Array Unique

Medium

946

Validate Stack Sequences

Medium

947

Most Stones Removed with Same Row or Column

Medium

948

Bag of Tokens

Medium

949

Largest Time for Given Digits

Medium

950

Reveal Cards In Increasing Order

Medium

951

Flip Equivalent Binary Trees

Medium

953

Verifying an Alien Dictionary

Easy

954

Array of Doubled Pairs

Medium

955

Delete Columns to Make Sorted II

Medium

957

Prison Cells After N Days

Medium

958

Check Completeness of a Binary Tree

Medium

959

Regions Cut By Slashes

Medium

960

Delete Columns to Make Sorted III

Hard

961

NRepeated Element in Size 2N Array

Easy

962

Maximum Width Ramp

Medium

963

Minimum Area Rectangle II

Medium

965

Univalued Binary Tree

Easy

966

Vowel Spellchecker

Medium

967

Numbers With Same Consecutive Differences

Medium

969

Pancake Sorting

Medium

970

Powerful Integers

Medium

971

Flip Binary Tree To Match Preorder Traversal

Medium

972

Equal Rational Numbers

Hard

973

K Closest Points to Origin

Medium

974

Subarray Sums Divisible by K

Medium

976

Largest Perimeter Triangle

Easy

977

Squares of a Sorted Array

Easy

978

Longest Turbulent Subarray

Medium

979

Distribute Coins in Binary Tree

Medium

980

Unique Paths III

Hard

981

Time Based KeyValue Store

Medium

982

Triples with Bitwise AND Equal To Zero

Hard

983

Minimum Cost For Tickets

Medium

984

String Without AAA or BBB

Medium

985

Sum of Even Numbers After Queries

Easy

986

Interval List Intersections

Medium

987

Vertical Order Traversal of a Binary Tree

Hard

988

Smallest String Starting From Leaf

Medium

989

Add to ArrayForm of Integer

Easy

990

Satisfiability of Equality Equations

Medium

991

Broken Calculator

Medium

992

Subarrays with K Different Integers

Hard

993

Cousins in Binary Tree

Easy

994

Rotting Oranges

Medium

995

Minimum Number of K Consecutive Bit Flips

Hard

997

Find the Town Judge

Easy

998

Maximum Binary Tree II

Medium

999

Available Captures for Rook

Easy

1002

Find Common Characters

Easy

1003

Check If Word Is Valid After Substitutions

Medium

1004

Max Consecutive Ones III

Medium

1005

Maximize Sum Of Array After K Negations

Easy

1006

Clumsy Factorial

Medium

1007

Minimum Domino Rotations For Equal Row

Medium

1008

Construct Binary Search Tree from Preorder Traversal

Medium

1009

Complement of Base 10 Integer

Easy

1010

Pairs of Songs With Total Durations Divisible by 60

Medium

1011

Capacity To Ship Packages Within D Days

Medium

1013

Partition Array Into Three Parts With Equal Sum

Easy

1014

Best Sightseeing Pair

Medium

1015

Smallest Integer Divisible by K

Medium

1016

Binary String With Substrings Representing 1 To N

Medium

1017

Convert to Base 2

Medium

1018

Binary Prefix Divisible By 5

Easy

1019

Next Greater Node In Linked List

Medium

1020

Number of Enclaves

Medium

1021

Remove Outermost Parentheses

Easy

1022

Sum of Root To Leaf Binary Numbers

Easy

1023

Camelcase Matching

Medium

1024

Video Stitching

Medium

1025

Divisor Game

Easy

1026

Maximum Difference Between Node and Ancestor

Medium

1027

Longest Arithmetic Subsequence

Medium

1028

Recover a Tree From Preorder Traversal

Hard

1029

Two City Scheduling

Medium

1030

Matrix Cells in Distance Order

Easy

1031

Maximum Sum of Two NonOverlapping Subarrays

Medium

1032

Stream of Characters

Hard

1033

Moving Stones Until Consecutive

Easy

1034

Coloring A Border

Medium

1035

Uncrossed Lines

Medium

1036

Escape a Large Maze

Hard

1037

Valid Boomerang

Easy

1038

Binary Search Tree to Greater Sum Tree

Medium

1039

Minimum Score Triangulation of Polygon

Medium

1040

Moving Stones Until Consecutive II

Medium

1041

Robot Bounded In Circle

Medium

1042

Flower Planting With No Adjacent

Medium

1043

Partition Array for Maximum Sum

Medium

1044

Longest Duplicate Substring

Hard

1046

Last Stone Weight

Easy

1047

Remove All Adjacent Duplicates In String

Easy

1048

Longest String Chain

Medium

1049

Last Stone Weight II

Medium

1051

Height Checker

Easy

1052

Grumpy Bookstore Owner

Medium

1053

Previous Permutation With One Swap

Medium

1054

Distant Barcodes

Medium

1055

Shortest Way to Form String

Medium

1056

Confusing Number

Easy

1057

Campus Bikes

Medium

1058

Minimize Rounding Error to Meet Target

Medium

1059

All Paths from Source Lead to Destination

Medium

1060

Missing Element in Sorted Array

Medium

1061

Lexicographically Smallest Equivalent String

Medium

1062

Longest Repeating Substring

Medium

1063

Number of Valid Subarrays

Hard

1064

Fixed Point

Easy

1065

Index Pairs of a String

Easy

1066

Campus Bikes II

Medium

1071

Greatest Common Divisor of Strings

Easy

1072

Flip Columns For Maximum Number of Equal Rows

Medium

1073

Adding Two Negabinary Numbers

Medium

1074

Number of Submatrices That Sum to Target

Hard

1078

Occurrences After Bigram

Easy

1079

Letter Tile Possibilities

Medium

1080

Insufficient Nodes in Root to Leaf Paths

Medium

1081

Smallest Subsequence of Distinct Characters

Medium

1085

Sum of Digits in the Minimum Number

Easy

1086

High Five

Easy

1087

Brace Expansion

Medium

1089

Duplicate Zeros

Easy

1090

Largest Values From Labels

Medium

1091

Shortest Path in Binary Matrix

Medium

1092

Shortest Common Supersequence

Hard

1093

Statistics from a Large Sample

Medium

1094

Car Pooling

Medium

1096

Brace Expansion II

Hard

1099

Two Sum Less Than K

Easy

1100

Find KLength Substrings With No Repeated Characters

Medium

1101

The Earliest Moment When Everyone Become Friends

Medium

1102

Path With Maximum Minimum Value

Medium

1103

Distribute Candies to People

Easy

1104

Path In Zigzag Labelled Binary Tree

Medium

1105

Filling Bookcase Shelves

Medium

1106

Parsing A Boolean Expression

Hard

1108

Defanging an IP Address

Easy

1109

Corporate Flight Bookings

Medium

1110

Delete Nodes And Return Forest

Medium

1111

Maximum Nesting Depth of Two Valid Parentheses Strings

Medium

1118

Number of Days in a Month

Easy

1119

Remove Vowels from a String

Easy

1120

Maximum Average Subtree

Medium

1121

Divide Array Into Increasing Sequences

Hard

1122

Relative Sort Array

Easy

1123

Lowest Common Ancestor of Deepest Leaves

Medium

1124

Longest WellPerforming Interval

Medium

1128

Number of Equivalent Domino Pairs

Easy

1129

Shortest Path with Alternating Colors

Medium

1130

Minimum Cost Tree From Leaf Values

Medium

1131

Maximum of Absolute Value Expression

Medium

1133

Largest Unique Number

Easy

1134

Armstrong Number

Easy

1135

Connecting Cities With Minimum Cost

Medium

1136

Parallel Courses

Medium

1137

Nth Tribonacci Number

Easy

1138

Alphabet Board Path

Medium

1139

Largest 1Bordered Square

Medium

1140

Stone Game II

Medium

1143

Longest Common Subsequence

Medium

1144

Decrease Elements To Make Array Zigzag

Medium

1145

Binary Tree Coloring Game

Medium

1146

Snapshot Array

Medium

1147

Longest Chunked Palindrome Decomposition

Hard

1150

Check If a Number Is Majority Element in a Sorted Array

Easy

1151

Minimum Swaps to Group All 1's Together

Medium

1152

Analyze User Website Visit Pattern

Medium

1154

Day of the Year

Easy

1155

Number of Dice Rolls With Target Sum

Medium

1156

Swap For Longest Repeated Character Substring

Medium

1160

Find Words That Can Be Formed by Characters

Easy

1161

Maximum Level Sum of a Binary Tree

Medium

1162

As Far from Land as Possible

Medium

1163

Last Substring in Lexicographical Order

Hard

1165

SingleRow Keyboard

Easy

1166

Design File System

Medium

1167

Minimum Cost to Connect Sticks

Medium

1168

Optimize Water Distribution in a Village

Hard

1169

Invalid Transactions

Medium

1170

Compare Strings by Frequency of the Smallest Character

Medium

1171

Remove Zero Sum Consecutive Nodes from Linked List

Medium

1172

Dinner Plate Stacks

Hard

1175

Prime Arrangements

Easy

1176

Diet Plan Performance

Easy

1177

Can Make Palindrome from Substring

Medium

1180

Count Substrings with Only One Distinct Letter

Easy

1181

Before and After Puzzle

Medium

1182

Shortest Distance to Target Color

Medium

1183

Maximum Number of Ones

Hard

1184

Distance Between Bus Stops

Easy

1185

Day of the Week

Easy

1186

Maximum Subarray Sum with One Deletion

Medium

1189

Maximum Number of Balloons

Easy

1190

Reverse Substrings Between Each Pair of Parentheses

Medium

1191

KConcatenation Maximum Sum

Medium

1192

Critical Connections in a Network

Hard

1196

How Many Apples Can You Put into the Basket

Easy

1197

Minimum Knight Moves

Medium

1198

Find Smallest Common Element in All Rows

Medium

1200

Minimum Absolute Difference

Easy

1201

Ugly Number III

Medium

1202

Smallest String With Swaps

Medium

1206

Design Skiplist

Hard

1207

Unique Number of Occurrences

Easy

1208

Get Equal Substrings Within Budget

Medium

1209

Remove All Adjacent Duplicates in String II

Medium

1210

Minimum Moves to Reach Target with Rotations

Hard

1213

Intersection of Three Sorted Arrays

Easy

1214

Two Sum BSTs

Medium

1215

Stepping Numbers

Medium

1216

Valid Palindrome III

Hard

1217

Minimum Cost to Move Chips to The Same Position

Easy

1218

Longest Arithmetic Subsequence of Given Difference

Medium

1219

Path with Maximum Gold

Medium

1220

Count Vowels Permutation

Hard

1221

Split a String in Balanced Strings

Easy

1222

Queens That Can Attack the King

Medium

1223

Dice Roll Simulation

Hard

1224

Maximum Equal Frequency

Hard

1227

Airplane Seat Assignment Probability

Medium

1228

Missing Number In Arithmetic Progression

Easy

1229

Meeting Scheduler

Medium

1230

Toss Strange Coins

Medium

1231

Divide Chocolate

Hard

1232

Check If It Is a Straight Line

Easy

1233

Remove SubFolders from the Filesystem

Medium

1234

Replace the Substring for Balanced String

Medium

1235

Maximum Profit in Job Scheduling

Hard

1237

Find Positive Integer Solution for a Given Equation

Medium

1238

Circular Permutation in Binary Representation

Medium

1239

Maximum Length of a Concatenated String with Unique Characters

Medium

1240

Tiling a Rectangle with the Fewest Squares

Hard

1243

Array Transformation

Easy

1244

Design A Leaderboard

Medium

1245

Tree Diameter

Medium

1246

Palindrome Removal

Hard

1247

Minimum Swaps to Make Strings Equal

Medium

1248

Count Number of Nice Subarrays

Medium

1249

Minimum Remove to Make Valid Parentheses

Medium

1250

Check If It Is a Good Array

Hard

1252

Cells with Odd Values in a Matrix

Easy

1253

Reconstruct a 2Row Binary Matrix

Medium

1254

Number of Closed Islands

Medium

1255

Maximum Score Words Formed by Letters

Hard

1256

Encode Number

Medium

1257

Smallest Common Region

Medium

1258

Synonymous Sentences

Medium

1259

Handshakes That Don't Cross

Hard

1260

Shift 2D Grid

Easy

1261

Find Elements in a Contaminated Binary Tree

Medium

1262

Greatest Sum Divisible by Three

Medium

1263

Minimum Moves to Move a Box to Their Target Location

Hard

1265

Print Immutable Linked List in Reverse

Medium

1266

Minimum Time Visiting All Points

Easy

1267

Count Servers that Communicate

Medium

1268

Search Suggestions System

Medium

1271

Hexspeak

Easy

1272

Remove Interval

Medium

1273

Delete Tree Nodes

Medium

1274

Number of Ships in a Rectangle

Hard

1275

Find Winner on a Tic Tac Toe Game

Easy

1276

Number of Burgers with No Waste of Ingredients

Medium

1277

Count Square Submatrices with All Ones

Medium

1278

Palindrome Partitioning III

Hard

1281

Subtract the Product and Sum of Digits of an Integer

Easy

1282

Group the People Given the Group Size They Belong To

Medium

1283

Find the Smallest Divisor Given a Threshold

Medium

1284

Minimum Number of Flips to Convert Binary Matrix to Zero Matrix

Hard

1286

Iterator for Combination

Medium

1287

Element Appearing More Than 25% In Sorted Array

Easy

1288

Remove Covered Intervals

Medium

1289

Minimum Falling Path Sum II

Hard

1290

Convert Binary Number in a Linked List to Integer

Easy

1291

Sequential Digits

Medium

1292

Maximum Side Length of a Square with Sum Less than or Equal to Threshold

Medium

1293

Shortest Path in a Grid with Obstacles Elimination

Hard

1295

Find Numbers with Even Number of Digits

Easy

1296

Divide Array in Sets of K Consecutive Numbers

Medium

1297

Maximum Number of Occurrences of a Substring

Medium

1298

Maximum Candies You Can Get from Boxes

Hard

1299

Replace Elements with Greatest Element on Right Side

Easy

1300

Sum of Mutated Array Closest to Target

Medium

1302

Deepest Leaves Sum

Medium

1304

Find N Unique Integers Sum up to Zero

Easy

1305

All Elements in Two Binary Search Trees

Medium

1306

Jump Game III

Medium

1309

Decrypt String from Alphabet to Integer Mapping

Easy

1310

XOR Queries of a Subarray

Medium

1311

Get Watched Videos by Your Friends

Medium

1312

Minimum Insertion Steps to Make a String Palindrome

Hard

1313

Decompress RunLength Encoded List

Easy

1314

Matrix Block Sum

Medium

1315

Sum of Nodes with EvenValued Grandparent

Medium

1316

Distinct Echo Substrings

Hard

1317

Convert Integer to the Sum of Two NoZero Integers

Easy

1318

Minimum Flips to Make a OR b Equal to c

Medium

1319

Number of Operations to Make Network Connected

Medium

1320

Minimum Distance to Type a Word Using Two Fingers

Hard

1323

Maximum 69 Number

Easy

1324

Print Words Vertically

Medium

1325

Delete Leaves With a Given Value

Medium

1326

Minimum Number of Taps to Open to Water a Garden

Hard

1328

Break a Palindrome

Medium

1329

Sort the Matrix Diagonally

Medium

1330

Reverse Subarray To Maximize Array Value

Hard

1331

Rank Transform of an Array

Easy

1332

Remove Palindromic Subsequences

Easy

1333

Filter Restaurants by VeganFriendly, Price and Distance

Medium

1334

Find the City With the Smallest Number of Neighbors at a Threshold Distance

Medium

1335

Minimum Difficulty of a Job Schedule

Hard

1337

The K Weakest Rows in a Matrix

Easy

1338

Reduce Array Size to The Half

Medium

1339

Maximum Product of Splitted Binary Tree

Medium

1340

Jump Game V

Hard

1342

Number of Steps to Reduce a Number to Zero

Easy

1343

Number of Subarrays of Size K and Average Greater than or Equal to Threshold

Medium

1344

Angle Between Hands of a Clock

Medium

1346

Check If N and Its Double Exist

Easy

1347

Minimum Number of Steps to Make Two Strings Anagram

Medium

1348

Tweet Counts Per Frequency

Medium

1351

Count Negative Numbers in a Sorted Matrix

Easy

1352

Product of the Last K Numbers

Medium

1353

Maximum Number of Events That Can Be Attended

Medium

1356

Sort Integers by The Number of 1 Bits

Easy

1357

Apply Discount Every n Orders

Medium

1358

Number of Substrings Containing All Three Characters

Medium

1359

Count All Valid Pickup and Delivery Options

Hard

1360

Number of Days Between Two Dates

Easy

1361

Validate Binary Tree Nodes

Medium

1362

Closest Divisors

Medium

1365

How Many Numbers Are Smaller Than the Current Number

Easy

1366

Rank Teams by Votes

Medium

1367

Linked List in Binary Tree

Medium

1368

Minimum Cost to Make at Least One Valid Path in a Grid

Hard

1370

Increasing Decreasing String

Easy

1371

Find the Longest Substring Containing Vowels in Even Counts

Medium

1372

Longest ZigZag Path in a Binary Tree

Medium

1374

Generate a String With Characters That Have Odd Counts

Easy

1375

Bulb Switcher III

Medium

1376

Time Needed to Inform All Employees

Medium

1377

Frog Position After T Seconds

Hard

1380

Lucky Numbers in a Matrix

Easy

1381

Design a Stack With Increment Operation

Medium

1382

Balance a Binary Search Tree

Medium

1383

Maximum Performance of a Team

Hard

1385

Find the Distance Value Between Two Arrays

Easy

1386

Cinema Seat Allocation

Medium

1387

Sort Integers by The Power Value

Medium

1389

Create Target Array in the Given Order

Easy

1390

Four Divisors

Medium

1391

Check if There is a Valid Path in a Grid

Medium

1394

Find Lucky Integer in an Array

Easy

1395

Count Number of Teams

Medium

1396

Design Underground System

Medium

1399

Count Largest Group

Easy

1428

Leftmost Column with at Least a One

Medium

1458

Max Dot Product of Two Subsequences

Hard

1494

Parallel Courses II

Hard

1499

Max Value of Equation

Hard

1531

String Compression II

Hard

1533

Find the Index of the Large Integer

Medium

1538

Guess the Majority in a Hidden Array

Medium

1591

Strange Printer II

Hard

1611

Minimum One Bit Operations to Make Integers Zero

Hard

1617

Count Subtrees With Max Distance Between Cities

Hard

1631

Path With Minimum Effort

Medium

1636

Sort Array by Increasing Frequency

Easy

1637

Widest Vertical Area Between Two Points Containing No Points

Medium

1638

Count Substrings That Differ by One Character

Medium

1640

Check Array Formation Through Concatenation

Easy

1641

Count Sorted Vowel Strings

Medium

1642

Furthest Building You Can Reach

Medium

1643

Kth Smallest Instructions

Hard

1646

Get Maximum in Generated Array

Easy

1647

Minimum Deletions to Make Character Frequencies Unique

Medium

1648

Sell DiminishingValued Colored Balls

Medium

1652

Defuse the Bomb

Easy

1653

Minimum Deletions to Make String Balanced

Medium

1654

Minimum Jumps to Reach Home

Medium

1656

Design an Ordered Stream

Easy

1657

Determine if Two Strings Are Close

Medium

1658

Minimum Operations to Reduce X to Zero

Medium

1659

Maximize Grid Happiness

Hard

1668

Maximum Repeating Substring

Easy

1669

Merge In Between Linked Lists

Medium

1670

Design Front Middle Back Queue

Medium

1671

Minimum Number of Removals to Make Mountain Array

Hard

1673

Find the Most Competitive Subsequence

Medium

1674

Minimum Moves to Make Array Complementary

Medium

1678

Goal Parser Interpretation

Easy

1679

Max Number of KSum Pairs

Medium

1680

Concatenation of Consecutive Binary Numbers

Medium

1681

Minimum Incompatibility

Hard

1682

Longest Palindromic Subsequence II

Medium

1684

Count the Number of Consistent Strings

Easy

1685

Sum of Absolute Differences in a Sorted Array

Medium

1686

Stone Game VI

Medium

1688

Count of Matches in Tournament

Easy

1689

Partitioning Into Minimum Number Of DeciBinary Numbers

Medium

1690

Stone Game VII

Medium

1691

Maximum Height by Stacking Cuboids

Hard

1692

Count Ways to Distribute Candies

Hard

1694

Reformat Phone Number

Easy

1695

Maximum Erasure Value

Medium

1696

Jump Game VI

Medium

1697

Checking Existence of Edge Length Limited Paths

Hard

1698

Number of Distinct Substrings in a String

Medium

1700

Number of Students Unable to Eat Lunch

Easy

1701

Average Waiting Time

Medium

1702

Maximum Binary String After Change

Medium

1704

Determine if String Halves Are Alike

Easy

1705

Maximum Number of Eaten Apples

Medium

1706

Where Will the Ball Fall

Medium

1708

Largest Subarray Length K

Easy

1710

Maximum Units on a Truck

Easy

1711

Count Good Meals

Medium

1712

Ways to Split Array Into Three Subarrays

Medium

1713

Minimum Operations to Make a Subsequence

Hard

1716

Calculate Money in Leetcode Bank

Easy

1717

Maximum Score From Removing Substrings

Medium

1718

Construct the Lexicographically Largest Valid Sequence

Medium

1720

Decode XORed Array

Easy

1721

Swapping Nodes in a Linked List

Medium

1722

Minimize Hamming Distance After Swap Operations

Medium

1725

Number Of Rectangles That Can Form The Largest Square

Easy

1726

Tuple with Same Product

Medium

1730

Shortest Path to Get Food

Medium

1732

Find the Highest Altitude

Easy

1733

Minimum Number of People to Teach

Medium

1734

Decode XORed Permutation

Medium

1736

Latest Time by Replacing Hidden Digits

Easy

1737

Change Minimum Characters to Satisfy One of Three Conditions

Medium

1738

Find Kth Largest XOR Coordinate Value

Medium

1740

Find Distance in a Binary Tree

Medium

1746

Maximum Subarray Sum After One Operation

Medium

1748

Sum of Unique Elements

Easy

1752

Check if Array Is Sorted and Rotated

Easy

1758

Minimum Changes To Make Alternating Binary String

Easy

1760

Minimum Limit of Balls in a Bag

Medium

1769

Minimum Number of Operations to Move All Balls to Each Box

Medium

1773

Count Items Matching a Rule

Easy

1779

Find Nearest Point That Has the Same X or Y Coordinate

Easy

1784

Check if Binary String Has at Most One Segment of Ones

Easy

1790

Check if One String Swap Can Make Strings Equal

Easy

1791

Find Center of Star Graph

Easy

1792

Maximum Average Pass Ratio

Medium

1794

Count Pairs of Equal Substrings With Minimum Difference

Medium

1796

Second Largest Digit in a String

Easy

1797

Design Authentication Manager

Medium

1798

Maximum Number of Consecutive Values You Can Make

Medium

1800

Maximum Ascending Subarray Sum

Easy

1801

Number of Orders in the Backlog

Medium

1802

Maximum Value at a Given Index in a Bounded Array

Medium

1804

Implement Trie II (Prefix Tree)

Medium

1805

Number of Different Integers in a String

Easy

1806

Minimum Number of Operations to Reinitialize a Permutation

Medium

1807

Evaluate the Bracket Pairs of a String

Medium

1810

Minimum Path Cost in a Hidden Grid

Medium

1812

Determine Color of a Chessboard Square

Easy

1813

Sentence Similarity III

Medium

1814

Count Nice Pairs in an Array

Medium

1816

Truncate Sentence

Easy

1817

Finding the Users Active Minutes

Medium

1818

Minimum Absolute Sum Difference

Medium

1820

Maximum Number of Accepted Invitations

Medium

1822

Sign of the Product of an Array

Easy

1823

Find the Winner of the Circular Game

Medium

1824

Minimum Sideway Jumps

Medium

1826

Faulty Sensor

Easy

1827

Minimum Operations to Make the Array Increasing

Easy

1828

Queries on Number of Points Inside a Circle

Medium

1829

Maximum XOR for Each Query

Medium

1832

Check if the Sentence Is Pangram

Easy

1833

Maximum Ice Cream Bars

Medium

1836

Remove Duplicates From an Unsorted Linked List

Medium

1837

Sum of Digits in Base K

Easy

1838

Frequency of the Most Frequent Element

Medium

1839

Longest Substring Of All Vowels in Order

Medium

1844

Replace All Digits with Characters

Easy

1848

Minimum Distance to the Target Element

Easy

1854

Maximum Population Year

Easy

1859

Sorting the Sentence

Easy

1863

Sum of All Subset XOR Totals

Easy

1869

Longer Contiguous Segments of Ones than Zeros

Easy

1876

Substrings of Size Three with Distinct Characters

Easy

1880

Check if Word Equals Summation of Two Words

Easy

1886

Determine Whether Matrix Can Be Obtained By Rotation

Easy

1893

Check if All the Integers in a Range Are Covered

Easy
