| 6 | ZigZag Conversion | Java & Python | Medium | Others |
| 9 | Palindrome Number | Java & Python | Easy | Others |
| 12 | Integer to Roman | Java & Python | Medium | Others |
| 16 | 3Sum Closest | Java & Python | Medium | Others |
| 18 | 4Sum | Java & Python | Medium | Others |
| 25 | Reverse Nodes in k-Group | Java & Python | Hard | Others |
| 30 | Substring with Concatenation of All Words | Java & Python | Hard | Others |
| 31 | Next Permutation | Java & Python | Medium | Others |
| 32 | Longest Valid Parentheses | Java & Python | Hard | Others |
| 35 | Search Insert Position | Java & Python | Easy | Others |
| 39 | Combination Sum | Java & Python | Medium | Others |
| 40 | Combination Sum II | Java & Python | Medium | Others |
| 43 | Multiply Strings | Java & Python | Medium | Others |
| 45 | Jump Game II | Java & Python | Hard | Others |
| 47 | Permutations II | Java & Python | Medium | Others |
| 51 | N-Queens | Java & Python | Hard | Others |
| 57 | Insert Interval | Java & Python | Hard | Others |
| 58 | Length of Last Word | Java & Python | Easy | Others |
| 59 | Spiral Matrix II | Java & Python | Medium | Others |
| 60 | Permutation Sequence | Java & Python | Medium | Others |
| 63 | Unique Paths II | Java & Python | Medium | Others |
| 64 | Minimum Path Sum | Java & Python | Medium | Others |
| 65 | Valid Number | Java & Python | Hard | Others |
| 68 | Text Justification | Java & Python | Hard | Others |
| 71 | Simplify Path | Java & Python | Medium | Others |
| 72 | Edit Distance | Java & Python | Hard | Others |
| 74 | Search a 2D Matrix | Java & Python | Medium | Others |
| 80 | Remove Duplicates from Sorted Array II | Java & Python | Medium | Others |
| 81 | Search in Rotated Sorted Array II | Java & Python | Medium | Others |
| 82 | Remove Duplicates from Sorted List II | Java & Python | Medium | Others |
| 83 | Remove Duplicates from Sorted List | Java & Python | Easy | Others |
| 85 | Maximal Rectangle | Java & Python | Hard | Others |
| 86 | Partition List | Java & Python | Medium | Others |
| 87 | Scramble String | Java & Python | Hard | Others |
| 89 | Gray Code | Java & Python | Medium | Others |
| 90 | Subsets II | Java & Python | Medium | Others |
| 92 | Reverse Linked List II | Java & Python | Medium | Others |
| 93 | Restore IP Addresses | Java & Python | Medium | Others |
| 96 | Unique Binary Search Trees | Java & Python | Medium | Others |
| 97 | Interleaving String | Java & Python | Hard | Others |
| 99 | Recover Binary Search Tree | Java & Python | Hard | Others |
| 107 | Binary Tree Level Order Traversal II | Java & Python | Easy | Others |
| 109 | Convert Sorted List to Binary Search Tree | Java & Python | Medium | Others |
| 111 | Minimum Depth of Binary Tree | Java & Python | Easy | Others |
| 113 | Path Sum II | Java & Python | Medium | Others |
| 114 | Flatten Binary Tree to Linked List | Java & Python | Medium | Others |
| 115 | Distinct Subsequences | Java & Python | Hard | Others |
| 120 | Triangle | Java & Python | Medium | Others |
| 123 | Best Time to Buy and Sell Stock III | Java & Python | Hard | Others |
| 126 | Word Ladder II | Java & Python | Hard | Others |
| 129 | Sum Root to Leaf Numbers | Java & Python | Medium | Others |
| 132 | Palindrome Partitioning II | Java & Python | Hard | Others |
| 134 | Gas Station | Java & Python | Medium | Others |
| 135 | Candy | Java & Python | Hard | Others |
| 137 | Single Number II | Java & Python | Medium | Others |
| 143 | Reorder List | Java & Python | Medium | Others |
| 147 | Insertion Sort List | Java & Python | Medium | Others |
| 164 | Maximum Gap | Java & Python | Hard | Others |
| 165 | Compare Version Numbers | Java & Python | Medium | Others |
| 168 | Excel Sheet Column Title | Java & Python | Easy | Others |
| 174 | Dungeon Game | Java & Python | Hard | Others |
| 187 | Repeated DNA Sequences | Java & Python | Medium | Others |
| 188 | Best Time to Buy and Sell Stock IV | Java & Python | Hard | Others |
| 199 | Binary Tree Right Side View | Java & Python | Medium | Others |
| 201 | Bitwise AND of Numbers Range | Java & Python | Medium | Others |
| 213 | House Robber II | Java & Python | Medium | Others |
| 214 | Shortest Palindrome | Java & Python | Hard | Others |
| 216 | Combination Sum III | Java & Python | Medium | Others |
| 221 | Maximal Square | Java & Python | Medium | Others |
| 222 | Count Complete Tree Nodes | Java & Python | Medium | Others |
| 223 | Rectangle Area | Java & Python | Medium | Others |
| 224 | Basic Calculator | Java & Python | Hard | Others |
| 226 | Invert Binary Tree | Java & Python | Easy | Others |
| 228 | Summary Ranges | Java & Python | Medium | Others |
| 229 | Majority Element II | Java & Python | Medium | Others |
| 231 | Power of Two | Java & Python | Easy | Others |
| 233 | Number of Digit One | Java & Python | Hard | Others |
| 241 | Different Ways to Add Parentheses | Java & Python | Medium | Others |
| 257 | Binary Tree Paths | Java & Python | Easy | Others |
| 258 | Add Digits | Java & Python | Easy | Others |
| 260 | Single Number III | Java & Python | Medium | Others |
| 263 | Ugly Number | Java & Python | Easy | Others |
| 264 | Ugly Number II | Java & Python | Medium | Others |
| 273 | Integer to English Words | Java & Python | Hard | Others |
| 274 | H-Index | Java & Python | Medium | Others |
| 275 | H-Index II | Java & Python | Medium | Others |
| 282 | Expression Add Operators | Java & Python | Hard | Others |
| 284 | Peeking Iterator | Java & Python | Medium | Others |
| 290 | Word Pattern | Java & Python | Easy | Others |
| 292 | Nim Game | Java & Python | Easy | Others |
| 299 | Bulls and Cows | Java & Python | Easy | Others |
| 303 | Range Sum Query - Immutable | Java & Python | Easy | Others |
| 304 | Range Sum Query 2D - Immutable | Java & Python | Medium | Others |
| 306 | Additive Number | Java & Python | Medium | Others |
| 307 | Range Sum Query - Mutable | Java & Python | Medium | Others |
| 310 | Minimum Height Trees | Java & Python | Medium | Others |
| 313 | Super Ugly Number | Java & Python | Medium | Others |
| 316 | Remove Duplicate Letters | Java & Python | Hard | Others |
| 318 | Maximum Product of Word Lengths | Java & Python | Medium | Others |
| 319 | Bulb Switcher | Java & Python | Medium | Others |
| 321 | Create Maximum Number | Java & Python | Hard | Others |
| 327 | Count of Range Sum | Java & Python | Hard | Others |
| 330 | Patching Array | Java & Python | Hard | Others |
| 331 | Verify Preorder Serialization of a Binary Tree | Java & Python | Medium | Others |
| 332 | Reconstruct Itinerary | Java & Python | Medium | Others |
| 335 | Self Crossing | Java & Python | Hard | Others |
| 337 | House Robber III | Java & Python | Medium | Others |
| 338 | Counting Bits | Java & Python | Medium | Others |
| 342 | Power of Four | Java & Python | Easy | Others |
| 343 | Integer Break | Java & Python | Medium | Others |
| 345 | Reverse Vowels of a String | Java & Python | Easy | Others |
| 352 | Data Stream as Disjoint Intervals | Java & Python | Hard | Others |
| 354 | Russian Doll Envelopes | Java & Python | Hard | Others |
| 355 | Design Twitter | Java & Python | Medium | Others |
| 357 | Count Numbers with Unique Digits | Java & Python | Medium | Others |
| 363 | Max Sum of Rectangle No Larger Than K | Java & Python | Hard | Others |
| 365 | Water and Jug Problem | Java & Python | Medium | Others |
| 368 | Largest Divisible Subset | Java & Python | Medium | Others |
| 372 | Super Pow | Java & Python | Medium | Others |
| 373 | Find K Pairs with Smallest Sums | Java & Python | Medium | Others |
| 375 | Guess Number Higher or Lower II | Java & Python | Medium | Others |
| 376 | Wiggle Subsequence | Java & Python | Medium | Others |
| 377 | Combination Sum IV | Java & Python | Medium | Others |
| 381 | Insert Delete GetRandom O(1) - Duplicates allowed | Java & Python | Hard | Others |
| 382 | Linked List Random Node | Java & Python | Medium | Others |
| 383 | Ransom Note | Java & Python | Easy | Others |
| 385 | Mini Parser | Java & Python | Medium | Others |
| 386 | Lexicographical Numbers | Java & Python | Medium | Others |
| 388 | Longest Absolute File Path | Java & Python | Medium | Others |
| 389 | Find the Difference | Java & Python | Easy | Others |
| 390 | Elimination Game | Java & Python | Medium | Others |
| 391 | Perfect Rectangle | Java & Python | Hard | Others |
| 392 | Is Subsequence | Java & Python | Easy | Others |
| 393 | UTF-8 Validation | Java & Python | Medium | Others |
| 395 | Longest Substring with At Least K Repeating Characters | Java & Python | Medium | Others |
| 396 | Rotate Function | Java & Python | Medium | Others |
| 397 | Integer Replacement | Java & Python | Medium | Others |
| 398 | Random Pick Index | Java & Python | Medium | Others |
| 399 | Evaluate Division | Java & Python | Medium | Others |
| 400 | Nth Digit | Java & Python | Medium | Others |
| 401 | Binary Watch | Java & Python | Easy | Others |
| 402 | Remove K Digits | Java & Python | Medium | Others |
| 403 | Frog Jump | Java & Python | Hard | Others |
| 404 | Sum of Left Leaves | Java & Python | Easy | Others |
| 405 | Convert a Number to Hexadecimal | Java & Python | Easy | Others |
| 407 | Trapping Rain Water II | Java & Python | Hard | Others |
| 409 | Longest Palindrome | Java & Python | Easy | Others |
| 413 | Arithmetic Slices | Java & Python | Medium | Others |
| 414 | Third Maximum Number | Java & Python | Easy | Others |
| 415 | Add Strings | Java & Python | Easy | Others |
| 416 | Partition Equal Subset Sum | Java & Python | Medium | Others |
| 417 | Pacific Atlantic Water Flow | Java & Python | Medium | Others |
| 419 | Battleships in a Board | Java & Python | Medium | Others |
| 420 | Strong Password Checker | Java & Python | Hard | Others |
| 423 | Reconstruct Original Digits from English | Java & Python | Medium | Others |
| 424 | Longest Repeating Character Replacement | Java & Python | Medium | Others |
| 427 | Construct Quad Tree | Java & Python | Medium | Others |
| 432 | All O`one Data Structure | Java & Python | Hard | Others |
| 433 | Minimum Genetic Mutation | Java & Python | Medium | Others |
| 434 | Number of Segments in a String | Java & Python | Easy | Others |
| 435 | Non-overlapping Intervals | Java & Python | Medium | Others |
| 436 | Find Right Interval | Java & Python | Medium | Others |
| 437 | Path Sum III | Java & Python | Easy | Others |
| 438 | Find All Anagrams in a String | Java & Python | Medium | Others |
| 440 | K-th Smallest in Lexicographical Order | Java & Python | Hard | Others |
| 441 | Arranging Coins | Java & Python | Easy | Others |
| 442 | Find All Duplicates in an Array | Java & Python | Medium | Others |
| 443 | String Compression | Java & Python | Easy | Others |
| 445 | Add Two Numbers II | Java & Python | Medium | Others |
| 446 | Arithmetic Slices II - Subsequence | Java & Python | Hard | Others |
| 447 | Number of Boomerangs | Java & Python | Easy | Others |
| 448 | Find All Numbers Disappeared in an Array | Java & Python | Easy | Others |
| 449 | Serialize and Deserialize BST | Java & Python | Medium | Others |
| 451 | Sort Characters By Frequency | Java & Python | Medium | Others |
| 452 | Minimum Number of Arrows to Burst Balloons | Java & Python | Medium | Others |
| 453 | Minimum Moves to Equal Array Elements | Java & Python | Easy | Others |
| 455 | Assign Cookies | Java & Python | Easy | Others |
| 456 | 132 Pattern | Java & Python | Medium | Others |
| 457 | Circular Array Loop | Java & Python | Medium | Others |
| 458 | Poor Pigs | Java & Python | Hard | Others |
| 459 | Repeated Substring Pattern | Java & Python | Easy | Others |
| 460 | LFU Cache | Java & Python | Hard | Others |
| 462 | Minimum Moves to Equal Array Elements II | Java & Python | Medium | Others |
| 463 | Island Perimeter | Java & Python | Easy | Others |
| 464 | Can I Win | Java & Python | Medium | Others |
| 466 | Count The Repetitions | Java & Python | Hard | Others |
| 467 | Unique Substrings in Wraparound String | Java & Python | Medium | Others |
| 468 | Validate IP Address | Java & Python | Medium | Others |
| 470 | Implement Rand10() Using Rand7() | Java & Python | Medium | Others |
| 472 | Concatenated Words | Java & Python | Hard | Others |
| 473 | Matchsticks to Square | Java & Python | Medium | Others |
| 474 | Ones and Zeroes | Java & Python | Medium | Others |
| 475 | Heaters | Java & Python | Easy | Others |
| 476 | Number Complement | Java & Python | Easy | Others |
| 477 | Total Hamming Distance | Java & Python | Medium | Others |
| 478 | Generate Random Point in a Circle | Java & Python | Medium | Others |
| 479 | Largest Palindrome Product | Java & Python | Hard | Others |
| 480 | Sliding Window Median | Java & Python | Hard | Others |
| 481 | Magical String | Java & Python | Medium | Others |
| 482 | License Key Formatting | Java & Python | Easy | Others |
| 483 | Smallest Good Base | Java & Python | Hard | Others |
| 486 | Predict the Winner | Java & Python | Medium | Others |
| 488 | Zuma Game | Java & Python | Hard | Others |
| 491 | Increasing Subsequences | Java & Python | Medium | Others |
| 492 | Construct the Rectangle | Java & Python | Easy | Others |
| 493 | Reverse Pairs | Java & Python | Hard | Others |
| 495 | Teemo Attacking | Java & Python | Medium | Others |
| 496 | Next Greater Element I | Java & Python | Easy | Others |
| 497 | Random Point in Non-overlapping Rectangles | Java & Python | Medium | Others |
| 500 | Keyboard Row | Java & Python | Easy | Others |
| 501 | Find Mode in Binary Search Tree | Java & Python | Easy | Others |
| 502 | IPO | Java & Python | Hard | Others |
| 503 | Next Greater Element II | Java & Python | Medium | Others |
| 504 | Base 7 | Java & Python | Easy | Others |
| 506 | Relative Ranks | Java & Python | Easy | Others |
| 507 | Perfect Number | Java & Python | Easy | Others |
| 508 | Most Frequent Subtree Sum | Java & Python | Medium | Others |
| 513 | Find Bottom Left Tree Value | Java & Python | Medium | Others |
| 514 | Freedom Trail | Java & Python | Hard | Others |
| 515 | Find Largest Value in Each Tree Row | Java & Python | Medium | Others |
| 516 | Longest Palindromic Subsequence | Java & Python | Medium | Others |
| 517 | Super Washing Machines | Java & Python | Hard | Others |
| 518 | Coin Change 2 | Java & Python | Medium | Others |
| 519 | Random Flip Matrix | Java & Python | Medium | Others |
| 520 | Detect Capital | Java & Python | Easy | Others |
| 521 | Longest Uncommon Subsequence I | Java & Python | Easy | Others |
| 522 | Longest Uncommon Subsequence II | Java & Python | Medium | Others |
| 523 | Continuous Subarray Sum | Java & Python | Medium | Others |
| 524 | Longest Word in Dictionary through Deleting | Java & Python | Medium | Others |
| 525 | Contiguous Array | Java & Python | Medium | Others |
| 526 | Beautiful Arrangement | Java & Python | Medium | Others |
| 528 | Random Pick with Weight | Java & Python | Medium | Others |
| 529 | Minesweeper | Java & Python | Medium | Others |
| 530 | Minimum Absolute Difference in BST | Java & Python | Easy | Others |
| 532 | K-diff Pairs in an Array | Java & Python | Easy | Others |
| 535 | Encode and Decode TinyURL | Java & Python | Medium | Others |
| 537 | Complex Number Multiplication | Java & Python | Medium | Others |
| 538 | Convert BST to Greater Tree | Java & Python | Easy | Others |
| 539 | Minimum Time Difference | Java & Python | Medium | Others |
| 540 | Single Element in a Sorted Array | Java & Python | Medium | Others |
| 541 | Reverse String II | Java & Python | Easy | Others |
| 543 | Diameter of Binary Tree | Java & Python | Easy | Others |
| 546 | Remove Boxes | Java & Python | Hard | Others |
| 551 | Student Attendance Record I | Java & Python | Easy | Others |
| 552 | Student Attendance Record II | Java & Python | Hard | Others |
| 553 | Optimal Division | Java & Python | Medium | Others |
| 554 | Brick Wall | Java & Python | Medium | Others |
| 556 | Next Greater Element III | Java & Python | Medium | Others |
| 558 | Quad Tree Intersection | Java & Python | Easy | Others |
| 560 | Subarray Sum Equals K | Java & Python | Medium | Others |
| 563 | Binary Tree Tilt | Java & Python | Easy | Others |
| 564 | Find the Closest Palindrome | Java & Python | Hard | Others |
| 565 | Array Nesting | Java & Python | Medium | Others |
| 566 | Reshape the Matrix | Java & Python | Easy | Others |
| 567 | Permutation in String | Java & Python | Medium | Others |
| 572 | Subtree of Another Tree | Java & Python | Easy | Others |
| 575 | Distribute Candies | Java & Python | Easy | Others |
| 576 | Out of Boundary Paths | Java & Python | Medium | Others |
| 581 | Shortest Unsorted Continuous Subarray | Java & Python | Easy | Others |
| 583 | Delete Operation for Two Strings | Java & Python | Medium | Others |
| 587 | Erect the Fence | Java & Python | Hard | Others |
| 591 | Tag Validator | Java & Python | Hard | Others |
| 592 | Fraction Addition and Subtraction | Java & Python | Medium | Others |
| 593 | Valid Square | Java & Python | Medium | Others |
| 594 | Longest Harmonious Subsequence | Java & Python | Easy | Others |
| 598 | Range Addition II | Java & Python | Easy | Others |
| 600 | Non-negative Integers without Consecutive Ones | Java & Python | Hard | Others |
| 605 | Can Place Flowers | Java & Python | Easy | Others |
| 606 | Construct String from Binary Tree | Java & Python | Easy | Others |
| 609 | Find Duplicate File in System | Java & Python | Medium | Others |
| 611 | Valid Triangle Number | Java & Python | Medium | Others |
| 617 | Merge Two Binary Trees | Java & Python | Easy | Others |
| 623 | Add One Row to Tree | Java & Python | Medium | Others |
| 628 | Maximum Product of Three Numbers | Java & Python | Easy | Others |
| 629 | K Inverse Pairs Array | Java & Python | Hard | Others |
| 630 | Course Schedule III | Java & Python | Hard | Others |
| 632 | Smallest Range Covering Elements from K Lists | Java & Python | Hard | Others |
| 633 | Sum of Square Numbers | Java & Python | Easy | Others |
| 636 | Exclusive Time of Functions | Java & Python | Medium | Others |
| 637 | Average of Levels in Binary Tree | Java & Python | Easy | Others |
| 638 | Shopping Offers | Java & Python | Medium | Others |
| 639 | Decode Ways II | Java & Python | Hard | Others |
| 640 | Solve the Equation | Java & Python | Medium | Others |
| 641 | Design Circular Deque | Java & Python | Medium | Others |
| 643 | Maximum Average Subarray I | Java & Python | Easy | Others |
| 645 | Set Mismatch | Java & Python | Easy | Others |
| 646 | Maximum Length of Pair Chain | Java & Python | Medium | Others |
| 647 | Palindromic Substrings | Java & Python | Medium | Others |
| 649 | Dota2 Senate | Java & Python | Medium | Others |
| 650 | 2 Keys Keyboard | Java & Python | Medium | Others |
| 653 | Two Sum IV - Input is a BST | Java & Python | Easy | Others |
| 654 | Maximum Binary Tree | Java & Python | Medium | Others |
| 655 | Print Binary Tree | Java & Python | Medium | Others |
| 657 | Robot Return to Origin | Java & Python | Easy | Others |
| 659 | Split Array into Consecutive Subsequences | Java & Python | Medium | Others |
| 661 | Image Smoother | Java & Python | Easy | Others |
| 662 | Maximum Width of Binary Tree | Java & Python | Medium | Others |
| 664 | Strange Printer | Java & Python | Hard | Others |
| 665 | Non-decreasing Array | Java & Python | Easy | Others |
| 667 | Beautiful Arrangement II | Java & Python | Medium | Others |
| 668 | Kth Smallest Number in Multiplication Table | Java & Python | Hard | Others |
| 669 | Trim a Binary Search Tree | Java & Python | Easy | Others |
| 670 | Maximum Swap | Java & Python | Medium | Others |
| 671 | Second Minimum Node In a Binary Tree | Java & Python | Easy | Others |
| 672 | Bulb Switcher II | Java & Python | Medium | Others |
| 673 | Number of Longest Increasing Subsequence | Java & Python | Medium | Others |
| 674 | Longest Continuous Increasing Subsequence | Java & Python | Easy | Others |
| 675 | Cut Off Trees for Golf Event | Java & Python | Hard | Others |
| 676 | Implement Magic Dictionary | Java & Python | Medium | Others |
| 678 | Valid Parenthesis String | Java & Python | Medium | Others |
| 679 | 24 Game | Java & Python | Hard | Others |
| 680 | Valid Palindrome II | Java & Python | Easy | Others |
| 682 | Baseball Game | Java & Python | Easy | Others |
| 684 | Redundant Connection | Java & Python | Medium | Others |
| 685 | Redundant Connection II | Java & Python | Hard | Others |
| 686 | Repeated String Match | Java & Python | Easy | Others |
| 687 | Longest Univalue Path | Java & Python | Easy | Others |
| 688 | Knight Probability in Chessboard | Java & Python | Medium | Others |
| 689 | Maximum Sum of 3 Non-Overlapping Subarrays | Java & Python | Hard | Others |
| 690 | Employee Importance | Java & Python | Easy | Others |
| 691 | Stickers to Spell Word | Java & Python | Hard | Others |
| 692 | Top K Frequent Words | Java & Python | Medium | Others |
| 693 | Binary Number with Alternating Bits | Java & Python | Easy | Others |
| 695 | Max Area of Island | Java & Python | Medium | Others |
| 696 | Count Binary Substrings | Java & Python | Easy | Others |
| 697 | Degree of an Array | Java & Python | Easy | Others |
| 698 | Partition to K Equal Sum Subsets | Java & Python | Medium | Others |
| 699 | Falling Squares | Java & Python | Hard | Others |
| 709 | To Lower Case | Java & Python | Easy | Others |
| 710 | Random Pick with Blacklist | Java & Python | Hard | Others |
| 712 | Minimum ASCII Delete Sum for Two Strings | Java & Python | Medium | Others |
| 713 | Subarray Product Less Than K | Java & Python | Medium | Others |
| 714 | Best Time to Buy and Sell Stock with Transaction Fee | Java & Python | Medium | Others |
| 715 | Range Module | Java & Python | Hard | Others |
| 717 | 1-bit and 2-bit Characters | Java & Python | Easy | Others |
| 718 | Maximum Length of Repeated Subarray | Java & Python | Medium | Others |
| 720 | Longest Word in Dictionary | Java & Python | Easy | Others |
| 721 | Accounts Merge | Java & Python | Medium | Others |
| 722 | Remove Comments | Java & Python | Medium | Others |
| 725 | Split Linked List in Parts | Java & Python | Medium | Others |
| 726 | Number of Atoms | Java & Python | Hard | Others |
| 728 | Self Dividing Numbers | Java & Python | Easy | Others |
| 729 | My Calendar I | Java & Python | Medium | Others |
| 730 | Count Different Palindromic Subsequences | Java & Python | Hard | Others |
| 731 | My Calendar II | Java & Python | Medium | Others |
| 732 | My Calendar III | Java & Python | Hard | Others |
| 735 | Asteroid Collision | Java & Python | Medium | Others |
| 736 | Parse Lisp Expression | Java & Python | Hard | Others |
| 738 | Monotone Increasing Digits | Java & Python | Medium | Others |
| 740 | Delete and Earn | Java & Python | Medium | Others |
| 741 | Cherry Pickup | Java & Python | Hard | Others |
| 743 | Network Delay Time | Java & Python | Medium | Others |
| 745 | Prefix and Suffix Search | Java & Python | Hard | Others |
| 746 | Min Cost Climbing Stairs | Java & Python | Easy | Others |
| 748 | Shortest Completing Word | Java & Python | Easy | Others |
| 749 | Contain Virus | Java & Python | Hard | Others |
| 753 | Cracking the Safe | Java & Python | Hard | Others |
| 754 | Reach a Number | Java & Python | Easy | Others |
| 756 | Pyramid Transition Matrix | Java & Python | Medium | Others |
| 757 | Set Intersection Size At Least Two | Java & Python | Hard | Others |
| 761 | Special Binary String | Java & Python | Hard | Others |
| 762 | Prime Number of Set Bits in Binary Representation | Java & Python | Easy | Others |
| 763 | Partition Labels | Java & Python | Medium | Others |
| 764 | Largest Plus Sign | Java & Python | Medium | Others |
| 765 | Couples Holding Hands | Java & Python | Hard | Others |
| 766 | Toeplitz Matrix | Java & Python | Easy | Others |
| 767 | Reorganize String | Java & Python | Medium | Others |
| 768 | Max Chunks To Make Sorted II | Java & Python | Hard | Others |
| 769 | Max Chunks To Make Sorted | Java & Python | Medium | Others |
| 770 | Basic Calculator IV | Java & Python | Hard | Others |
| 773 | Sliding Puzzle | Java & Python | Hard | Others |
| 775 | Global and Local Inversions | Java & Python | Medium | Others |
| 777 | Swap Adjacent in LR String | Java & Python | Medium | Others |
| 778 | Swim in Rising Water | Java & Python | Hard | Others |
| 780 | Reaching Points | Java & Python | Hard | Others |
| 781 | Rabbits in Forest | Java & Python | Medium | Others |
| 782 | Transform to Chessboard | Java & Python | Hard | Others |
| 783 | Minimum Distance Between BST Nodes | Java & Python | Easy | Others |
| 784 | Letter Case Permutation | Java & Python | Easy | Others |
| 785 | Is Graph Bipartite? | Java & Python | Medium | Others |
| 786 | K-th Smallest Prime Fraction | Java & Python | Hard | Others |
| 787 | Cheapest Flights Within K Stops | Java & Python | Medium | Others |
| 788 | Rotated Digits | Java & Python | Easy | Others |
| 789 | Escape The Ghosts | Java & Python | Medium | Others |
| 790 | Domino and Tromino Tiling | Java & Python | Medium | Others |
| 791 | Custom Sort String | Java & Python | Medium | Others |
| 792 | Number of Matching Subsequences | Java & Python | Medium | Others |
| 793 | Preimage Size of Factorial Zeroes Function | Java & Python | Hard | Others |
| 794 | Valid Tic-Tac-Toe State | Java & Python | Medium | Others |
| 795 | Number of Subarrays with Bounded Maximum | Java & Python | Medium | Others |
| 796 | Rotate String | Java & Python | Easy | Others |
| 797 | All Paths From Source to Target | Java & Python | Medium | Others |
| 798 | Smallest Rotation with Highest Score | Java & Python | Hard | Others |
| 799 | Champagne Tower | Java & Python | Medium | Others |
| 801 | Minimum Swaps To Make Sequences Increasing | Java & Python | Medium | Others |
| 802 | Find Eventual Safe States | Java & Python | Medium | Others |
| 803 | Bricks Falling When Hit | Java & Python | Hard | Others |
| 804 | Unique Morse Code Words | Java & Python | Easy | Others |
| 805 | Split Array With Same Average | Java & Python | Hard | Others |
| 806 | Number of Lines To Write String | Java & Python | Easy | Others |
| 807 | Max Increase to Keep City Skyline | Java & Python | Medium | Others |
| 808 | Soup Servings | Java & Python | Medium | Others |
| 809 | Expressive Words | Java & Python | Medium | Others |
| 810 | Chalkboard XOR Game | Java & Python | Hard | Others |
| 811 | Subdomain Visit Count | Java & Python | Easy | Others |
| 812 | Largest Triangle Area | Java & Python | Easy | Others |
| 813 | Largest Sum of Averages | Java & Python | Medium | Others |
| 814 | Binary Tree Pruning | Java & Python | Medium | Others |
| 815 | Bus Routes | Java & Python | Hard | Others |
| 816 | Ambiguous Coordinates | Java & Python | Medium | Others |
| 817 | Linked List Components | Java & Python | Medium | Others |
| 818 | Race Car | Java & Python | Hard | Others |
| 819 | Most Common Word | Java & Python | Easy | Others |
| 820 | Short Encoding of Words | Java & Python | Medium | Others |
| 821 | Shortest Distance to a Character | Java & Python | Easy | Others |
| 822 | Card Flipping Game | Java & Python | Medium | Others |
| 823 | Binary Trees With Factors | Java & Python | Medium | Others |
| 824 | Goat Latin | Java & Python | Easy | Others |
| 825 | Friends Of Appropriate Ages | Java & Python | Medium | Others |
| 826 | Most Profit Assigning Work | Java & Python | Medium | Others |
| 827 | Making A Large Island | Java & Python | Hard | Others |
| 828 | Unique Letter String | Java & Python | Hard | Others |
| 829 | Consecutive Numbers Sum | Java & Python | Hard | Others |
| 830 | Positions of Large Groups | Java & Python | Easy | Others |
| 831 | Masking Personal Information | Java & Python | Medium | Others |
| 832 | Flipping an Image | Java & Python | Easy | Others |
| 833 | Find And Replace in String | Java & Python | Medium | Others |
| 834 | Sum of Distances in Tree | Java & Python | Hard | Others |
| 835 | Image Overlap | Java & Python | Medium | Others |
| 836 | Rectangle Overlap | Java & Python | Easy | Others |
| 837 | New 21 Game | Java & Python | Medium | Others |
| 838 | Push Dominoes | Java & Python | Medium | Others |
| 839 | Similar String Groups | Java & Python | Hard | Others |
| 840 | Magic Squares In Grid | Java & Python | Easy | Others |
| 842 | Split Array into Fibonacci Sequence | Java & Python | Medium | Others |
| 843 | Guess the Word | Java & Python | Hard | Others |
| 844 | Backspace String Compare | Java & Python | Easy | Others |
| 845 | Longest Mountain in Array | Java & Python | Medium | Others |
| 846 | Hand of Straights | Java & Python | Medium | Others |
| 847 | Shortest Path Visiting All Nodes | Java & Python | Hard | Others |
| 848 | Shifting Letters | Java & Python | Medium | Others |
| 849 | Maximize Distance to Closest Person | Java & Python | Easy | Others |
| 850 | Rectangle Area II | Java & Python | Hard | Others |
| 851 | Loud and Rich | Java & Python | Medium | Others |
| 852 | Peak Index in a Mountain Array | Java & Python | Easy | Others |
| 853 | Car Fleet | Java & Python | Medium | Others |
| 854 | K-Similar Strings | Java & Python | Hard | Others |
| 855 | Exam Room | Java & Python | Medium | Others |
| 856 | Score of Parentheses | Java & Python | Medium | Others |
| 857 | Minimum Cost to Hire K Workers | Java & Python | Hard | Others |
| 858 | Mirror Reflection | Java & Python | Medium | Others |
| 859 | Buddy Strings | Java & Python | Easy | Others |
| 860 | Lemonade Change | Java & Python | Easy | Others |
| 861 | Score After Flipping Matrix | Java & Python | Medium | Others |
| 862 | Shortest Subarray with Sum at Least K | Java & Python | Hard | Others |
| 863 | All Nodes Distance K in Binary Tree | Java & Python | Medium | Others |
| 864 | Shortest Path to Get All Keys | Java & Python | Hard | Others |
| 865 | Smallest Subtree with all the Deepest Nodes | Java & Python | Medium | Others |
| 866 | Prime Palindrome | Java & Python | Medium | Others |
| 867 | Transpose Matrix | Java & Python | Easy | Others |
| 868 | Binary Gap | Java & Python | Easy | Others |
| 869 | Reordered Power of 2 | Java & Python | Medium | Others |
| 870 | Advantage Shuffle | Java & Python | Medium | Others |
| 871 | Minimum Number of Refueling Stops | Java & Python | Hard | Others |
| 872 | Leaf-Similar Trees | Java & Python | Easy | Others |
| 873 | Length of Longest Fibonacci Subsequence | Java & Python | Medium | Others |
| 874 | Walking Robot Simulation | Java & Python | Easy | Others |
| 875 | Koko Eating Bananas | Java & Python | Medium | Others |
| 876 | Middle of the Linked List | Java & Python | Easy | Others |
| 877 | Stone Game | Java & Python | Medium | Others |
| 878 | Nth Magical Number | Java & Python | Hard | Others |
| 879 | Profitable Schemes | Java & Python | Hard | Others |
| 880 | Decoded String at Index | Java & Python | Medium | Others |
| 881 | Boats to Save People | Java & Python | Medium | Others |
| 882 | Reachable Nodes In Subdivided Graph | Java & Python | Hard | Others |
| 883 | Projection Area of 3D Shapes | Java & Python | Easy | Others |
| 884 | Uncommon Words from Two Sentences | Java & Python | Easy | Others |
| 885 | Spiral Matrix III | Java & Python | Medium | Others |
| 886 | Possible Bipartition | Java & Python | Medium | Others |
| 887 | Super Egg Drop | Java & Python | Hard | Others |
| 888 | Fair Candy Swap | Java & Python | Easy | Others |
| 889 | Construct Binary Tree from Preorder and Postorder Traversal | Java & Python | Medium | Others |
| 890 | Find and Replace Pattern | Java & Python | Medium | Others |
| 891 | Sum of Subsequence Widths | Java & Python | Hard | Others |
| 892 | Surface Area of 3D Shapes | Java & Python | Easy | Others |
| 893 | Groups of Special-Equivalent Strings | Java & Python | Easy | Others |
| 894 | All Possible Full Binary Trees | Java & Python | Medium | Others |
| 895 | Maximum Frequency Stack | Java & Python | Hard | Others |
| 896 | Monotonic Array | Java & Python | Easy | Others |
| 897 | Increasing Order Search Tree | Java & Python | Easy | Others |
| 898 | Bitwise ORs of Subarrays | Java & Python | Medium | Others |
| 899 | Orderly Queue | Java & Python | Hard | Others |
| 900 | RLE Iterator | Java & Python | Medium | Others |
| 901 | Online Stock Span | Java & Python | Medium | Others |
| 902 | Numbers At Most N Given Digit Set | Java & Python | Hard | Others |
| 903 | Valid Permutations for DI Sequence | Java & Python | Hard | Others |
| 904 | Fruit Into Baskets | Java & Python | Medium | Others |
| 905 | Sort Array By Parity | Java & Python | Easy | Others |
| 906 | Super Palindromes | Java & Python | Hard | Others |
| 907 | Sum of Subarray Minimums | Java & Python | Medium | Others |
| 908 | Smallest Range I | Java & Python | Easy | Others |
| 909 | Snakes and Ladders | Java & Python | Medium | Others |
| 910 | Smallest Range II | Java & Python | Medium | Others |
| 911 | Online Election | Java & Python | Medium | Others |
| 913 | Cat and Mouse | Java & Python | Hard | Others |
| 914 | X of a Kind in a Deck of Cards | Java & Python | Easy | Others |
| 915 | Partition Array into Disjoint Intervals | Java & Python | Medium | Others |
