| 368 | Largest Divisible Subset | ArrayMathDynamic Programming+1 | Medium |
| 371 | Sum of Two Integers | MathBit Manipulation | Medium |
| 372 | Super Pow | MathDivide and Conquer | Medium |
| 373 | Find K Pairs with Smallest Sums | ArrayHeap (Priority Queue) | Medium |
| 374 | Guess Number Higher or Lower | Binary SearchInteractive | Easy |
| 375 | Guess Number Higher or Lower II | MathDynamic ProgrammingGame Theory | Medium |
| 376 | Wiggle Subsequence | ArrayDynamic ProgrammingGreedy | Medium |
| 377 | Combination Sum IV | ArrayDynamic Programming | Medium |
| 378 | Kth Smallest Element in a Sorted Matrix | ArrayBinary SearchSorting+2 | Medium |
| 380 | Insert Delete GetRandom O(1) | ArrayHash TableMath+2 | Medium |
| 381 | Insert Delete GetRandom O(1) - Duplicates allowed | ArrayHash TableMath+2 | Hard |
| 382 | Linked List Random Node | Linked ListMathReservoir Sampling+1 | Medium |
| 383 | Ransom Note | Hash TableStringCounting | Easy |
| 384 | Shuffle an Array | ArrayMathDesign+1 | Medium |
| 385 | Mini Parser | StringStackDepth-First Search | Medium |
| 386 | Lexicographical Numbers | Depth-First SearchTrie | Medium |
| 387 | First Unique Character in a String | Hash TableStringQueue+1 | Easy |
| 388 | Longest Absolute File Path | StringStackDepth-First Search | Medium |
| 389 | Find the Difference | Hash TableStringBit Manipulation+1 | Easy |
| 390 | Elimination Game | MathRecursion | Medium |
| 391 | Perfect Rectangle | ArrayHash TableMath+2 | Hard |
| 392 | Is Subsequence | Two PointersStringDynamic Programming | Easy |
| 393 | UTF-8 Validation | ArrayBit Manipulation | Medium |
| 394 | Decode String | StringStackRecursion | Medium |
| 395 | Longest Substring with At Least K Repeating Characters | Hash TableStringDivide and Conquer+1 | Medium |
| 396 | Rotate Function | ArrayMathDynamic Programming | Medium |
| 397 | Integer Replacement | Dynamic ProgrammingGreedyBit Manipulation+1 | Medium |
| 398 | Random Pick Index | Hash TableMathReservoir Sampling+1 | Medium |
| 399 | Evaluate Division | ArrayStringDepth-First Search+4 | Medium |
| 400 | Nth Digit | MathBinary Search | Medium |
| 401 | Binary Watch | BacktrackingBit Manipulation | Easy |
| 402 | Remove K Digits | StringStackGreedy+1 | Medium |
| 403 | Frog Jump | ArrayDynamic Programming | Hard |
| 404 | Sum of Left Leaves | TreeDepth-First SearchBreadth-First Search+1 | Easy |
| 405 | Convert a Number to Hexadecimal | MathStringBit Manipulation | Easy |
| 406 | Queue Reconstruction by Height | ArrayBinary Indexed TreeSegment Tree+1 | Medium |
| 407 | Trapping Rain Water II | ArrayBreadth-First SearchHeap (Priority Queue)+1 | Hard |
| 409 | Longest Palindrome | Hash TableStringGreedy | Easy |
| 410 | Split Array Largest Sum | ArrayBinary SearchDynamic Programming+2 | Hard |
| 412 | Fizz Buzz | MathStringSimulation | Easy |
| 413 | Arithmetic Slices | ArrayDynamic ProgrammingSliding Window | Medium |
| 414 | Third Maximum Number | ArraySorting | Easy |
| 415 | Add Strings | MathStringSimulation | Easy |
| 416 | Partition Equal Subset Sum | ArrayDynamic Programming | Medium |
| 417 | Pacific Atlantic Water Flow | ArrayDepth-First SearchBreadth-First Search+1 | Medium |
| 419 | Battleships in a Board | ArrayDepth-First SearchMatrix | Medium |
| 420 | Strong Password Checker | StringGreedyHeap (Priority Queue) | Hard |
| 421 | Maximum XOR of Two Numbers in an Array | ArrayHash TableBit Manipulation+1 | Medium |
| 423 | Reconstruct Original Digits from English | Hash TableMathString | Medium |
| 424 | Longest Repeating Character Replacement | Hash TableStringSliding Window | Medium |