| 102 | Binary Tree Level Order Traversal | Easy | breadth first search |
| 103 | Binary Tree Zigzag Level Order Traversal | Medium | breadth first search |
| 107 | Binary Tree Level Order Traversal II | Easy | breadth first search |
| 117 | Populating Next Right Pointers in Each Node II | Hard | breadth first search |
| 127 | Word Ladder | Medium | breadth first search |
| 130 | Surrounded Regions | Medium | breadth first search |
| 133 | Clone Graph | Medium | breadth first search |
| 200 | Number of Islands | Medium | depth first search |
| 207 | Course Schedule | Medium | breadth first search |
| 210 | Course Schedule II | Medium | breadth first search |
| 239 | Sliding Window Maximum | Hard | queue |
| 261 | Graph Valid Tree | Medium | breadth first search |
| 269 | Alien Dictionary | Hard | breadth first search |
| 281 | Zigzag Iterator | Medium | queue |
| 286 | Walls and Gates | Medium | breadth first search |
| 310 | Minimum Height Trees | Medium | breadth first search |
| 314 | Binary Tree Vertical Order Traversal | Medium | hash table |
| 317 | Shortest Distance from All Buildings | Hard | breadth first search |
| 346 | Moving Average from Data Stream | Easy | queue |
| 399 | Evaluate Division | Medium | graph |
| 433 | Minimum Genetic Mutation | Medium | breadth first search |
| 490 | The Maze | Medium | breadth first search |
| 499 | The Maze III | Hard | breadth first search |
| 505 | The Maze II | Medium | breadth first search |
| 513 | Find Bottom Left Tree Value | Medium | tree |
| 582 | Kill Process | Medium | depth first search |
| 690 | Employee Importance | Easy | depth first search |
| 742 | Closest Leaf in a Binary Tree | Medium | breadth first search |
| 743 | Network Delay Time | Medium | breadth first search |
| 752 | Open the Lock | Medium | breadth first search |
| 787 | Cheapest Flights Within K Stops | Medium | breadth first search |
| 815 | Bus Routes | Medium | breadth first search |
| 847 | Shortest Path Visiting All Nodes | Hard | dynamic programming |
| 854 | K-Similar Strings | Hard | breadth first search |
| 882 | Reachable Nodes In Subdivided Graph | Medium | breadth first search |
| 886 | Possible Bipartition | Medium | breadth first search |
| 933 | Number of Recent Calls | Easy | queue |
| 934 | Shortest Bridge | Medium | breadth first search |
| 958 | Check Completeness of a Binary Tree | Medium | tree |
| 967 | Numbers With Same Consecutive Differences | Medium | breadth first search |
| 994 | Rotting Oranges | Easy | breadth first search |
| 1034 | Coloring A Border | Medium | breadth first search |
| 1036 | Escape a Large Maze | Hard | breadth first search |
| 1091 | Shortest Path in Binary Matrix | Medium | breadth first search |
| 1129 | Shortest Path with Alternating Colors | Medium | breadth first search |
| 1136 | Parallel Courses | Medium | breadth first search |
| 1162 | As Far from Land as Possible | Medium | breadth first search |
| 1210 | Minimum Moves to Reach Target with Rotations | Hard | breadth first search |
| 1245 | Tree Diameter | Medium | breadth first search |
| 1284 | Minimum Number of Flips to Convert Binary Matrix to Zero Matrix | Hard | breadth first search |
| 1291 | Sequential Digits | Medium | breadth first search |
| 1298 | Maximum Candies You Can Get from Boxes | Hard | breadth first search |
| 1302 | Deepest Leaves Sum | Medium | breadth first search |
| 1306 | Jump Game III | Medium | breadth first search |
| 1311 | Get Watched Videos by Your Friends | Medium | breadth first search |
| 1345 | Jump Game IV | Hard | breadth first search |
| 1377 | Frog Position After T Seconds | Hard | depth first search |
| 1424 | Diagonal Traverse II | Medium | queue |
| 1430 | Check If a String Is a Valid Sequence from Root to Leaves Path in a Binary Tree | Medium | tree |
| 1438 | Longest Continuous Subarray With Absolute Diff Less Than or Equal to Limit | Hard | queue |
| 1499 | Max Value of Equation | Hard | queue |
| 1514 | Path with Maximum Probability | Medium | breadth first search |
| 1559 | Detect Cycles in 2D Grid | Hard | array |
| 1602 | Find Nearest Right Node in Binary Tree | Medium | breadth first search |
| 1609 | Even Odd Tree | Medium | breadth first search |
| 1625 | Lexicographically Smallest String After Applying Operations | Medium | breadth first search |
| 1631 | Path With Minimum Effort | Medium | graph |
| 1654 | Minimum Jumps to Reach Home | Medium | breadth first search |
| 1660 | Correct a Binary Tree | Medium | breadth first search |
| 1730 | Shortest Path to Get Food | Medium | breadth first search |
| 1765 | Map of Highest Peak | Medium | breadth first search |
| 1778 | Shortest Path in a Hidden Grid | Medium | graph |
| 1871 | Jump Game VII | Medium | dynamic programming |
| 1926 | Nearest Exit from Entrance in Maze | Medium | breadth first search |
| 1928 | Minimum Cost to Reach Destination in Time | Medium | breadth first search |
| 1932 | Merge BSTs to Create Single BST | Hard | binary search tree |
| 2039 | The Time When the Network Becomes Idle | Medium | breadth first search |
| 2045 | Second Minimum Time to Reach Destination | Medium | breadth first search |
| 2050 | Parallel Courses III | Medium | breadth first search |
| 2059 | Minimum Operations to Convert Number | Medium | breadth first search |
| 2092 | Find All People With Secret | Hard | graph |
| 2115 | Find All Possible Recipes from Given Supplies | Medium | breadth first search |
| 2146 | K Highest Ranked Items Within a Price Range | Medium | breadth first search |
| 2246 | Longest Path With Different Adjacent Characters | Hard | depth first search |
| 2247 | Maximum Cost of Trip With K Highways | Hard | dynamic programming |
| 2258 | Escape the Spreading Fire | Hard | breadth first search |
| 2277 | Closest Node to Path in Tree | Hard | tree |
| 2316 | Count Unreachable Pairs of Nodes in an Undirected Graph | Medium | breadth first search |
| 2368 | Reachable Nodes With Restrictions | Medium | breadth first search |
| 2385 | Amount of Time for Binary Tree to Be Infected | Medium | depth first search |
| 2386 | Find the K-Sum of an Array | Hard | binary heap |
| 2415 | Reverse Odd Levels of Binary Tree | Medium | breadth first search |
| 2440 | Create Components With Same Value | Hard | greedy |
| 2445 | Number of Nodes With Value One | Medium | depth first search |
| 2471 | Minimum Number of Operations to Sort a Binary Tree by Level | Medium | breadth first search |
| 2492 | Minimum Score of a Path Between Two Cities | Medium | breadth first search |
| 2493 | Divide Nodes Into the Maximum Number of Groups | Medium | breadth first search |
| 2503 | Maximum Number of Points From Grid Queries | Hard | breadth first search |
| 2583 | Kth Largest Sum in a Binary Tree | Medium | breadth first search |
| 2603 | Collect Coins in a Tree | Hard | breadth first search |
| 2608 | Shortest Cycle in a Graph | Hard | graph |
| 2612 | Minimum Reverse Operations | Hard | breadth first search |
| 2617 | Minimum Number of Visited Cells in a Grid | Hard | breadth first search |
| 2641 | Cousins in Binary Tree II | Medium | breadth first search |
| 2658 | Maximum Number of Fish in a Grid | Medium | breadth first search |
| 2684 | Maximum Number of Moves in a Grid | Medium | dynamic programming |
| 2685 | Count the Number of Complete Components | Medium | breadth first search |
| 2709 | Greatest Common Divisor Traversal | Hard | breadth first search |
| 2773 | Height of Special Binary Tree | Medium | depth first search |
| 2812 | Find the Safest Path in a Grid | Medium | breadth first search |
| 2814 | Minimum Time Takes to Reach Destination Without Drowning | Hard | breadth first search |
| 2852 | Sum of Remoteness of All Cells | Medium | breadth first search |
| 2872 | Maximum Number of K-Divisible Components | Hard | greedy |
| 2998 | Minimum Number of Operations to Make X and Y Equal | Medium | dynamic programming |
| 3067 | Count Pairs of Connectable Servers in a Weighted Tree Network | Medium | depth first search |
| 3141 | Maximum Hamming Distances | Hard | dynamic programming |
| 3157 | Find the Level of Tree with Minimum Sum | Medium | breadth first search |
| 3203 | Find Minimum Diameter After Merging Two Trees | Hard | depth first search |
| 3211 | Generate Binary Strings Without Adjacent Zeros | Medium | backtracking |
| 3235 | Check if the Rectangle Corner Is Reachable | Hard | graph |
| 3236 | CEO Subordinate Hierarchy | Hard | sql |
| 3241 | Time Taken to Mark All Nodes | Hard | dynamic programming |
| 3243 | Shortest Distance After Road Addition Queries I | Medium | graph |
| 3265 | Count Almost Equal Pairs I | Medium | graph |
| 3267 | Count Almost Equal Pairs II | Hard | graph |
| 3283 | Maximum Number of Moves to Kill All Pawns | Hard | dynamic programming |
| 3286 | Find a Safe Walk Through a Grid | Medium | breadth first search |
| 3310 | Remove Methods From Project | Medium | graph |
| 3311 | Construct 2D Grid Matching Graph Layout | Hard | constructive algorithms |
| 3313 | Find the Last Marked Nodes in Tree | Hard | dynamic programming |
| 3372 | Maximize the Number of Target Nodes After Connecting Trees I | Medium | dynamic programming |
| 3373 | Maximize the Number of Target Nodes After Connecting Trees II | Hard | breadth first search |
| 3387 | Maximize Amount After Two Days of Conversions | Medium | graph |
| 3419 | Minimize the Maximum Edge Weight of Graph | Medium | graph |
| 3482 | Analyze Organization Hierarchy | Hard | sql |
| 3493 | Properties Graph | Medium | graph |
| 3528 | Unit Conversion I | Medium | breadth first search |
| 3535 | Unit Conversion II | Medium | breadth first search |
| 3547 | Maximum Sum of Edge Values in a Graph | Hard | graph |
| 3552 | Grid Teleportation Traversal | Medium | breadth first search |
| 3558 | Number of Ways to Assign Edge Weights I | Medium | tree |
| 3568 | Minimum Moves to Clean the Classroom | Medium | breadth first search |
| 3619 | Count Islands With Total Value Divisible by K | Medium | breadth first search |
| 3629 | Minimum Jumps to Reach End via Prime Teleportation | Medium | breadth first search |
| 3690 | Split and Merge Array Transformation | Medium | breadth first search |
| 3695 | Maximize Alternating Sum Using Swaps | Hard | breadth first search |
| 3710 | Maximum Partition Factor | Hard | graph |
| 3772 | Maximum Subgraph Score in a Tree | Hard | dynamic programming |
| 3786 | Total Sum of Interaction Cost in Tree Groups | Hard | breadth first search |
| 3787 | Find Diameter Endpoints of a Tree | Medium | breadth first search |
| 3807 | Minimum Cost to Repair Edges to Traverse a Graph | Medium | binary search |
| 3820 | Pythagorean Distance Nodes in a Tree | Medium | breadth first search |
| 3831 | Median of a Binary Search Tree Level | Medium | breadth first search |
| 3869 | Count Fancy Numbers in a Range | Hard | dynamic programming |
| 3877 | Minimum Removals to Achieve Target XOR | Medium | dynamic programming |
| 3879 | Maximum Distinct Path Sum in a Binary Tree | Medium | tree |
| 3902 | Zigzag Level Sum of Binary Tree | Hard | breadth first search |
| 3905 | Multi Source Flood Fill | Medium | breadth first search |
| 3923 | Minimum Generations to Target Point | Medium | breadth first search |
| 3991 | Sort Array Using Prefix Reversals | Medium | breadth first search |