| 16 |
Binary Tree Level Order Traversal II |
Medium |
TreeBreadth-First SearchBinary Tree |
| 17 |
Binary Tree Longest Consecutive Sequence |
Medium |
TreeDepth-First SearchBinary Tree |
| 18 |
Binary Tree Longest Consecutive Sequence II |
Medium |
TreeDepth-First SearchBinary Tree |
| 19 |
Binary Tree Maximum Path Sum |
Hard |
Dynamic ProgrammingTreeDepth-First Search |
| 20 |
Binary Tree Mirror |
Medium |
TreesBinary TreeRecursion |
| 21 |
Binary Tree Paths |
Easy |
StringBacktrackingTree |
| 22 |
Binary Tree Postorder Traversal |
Easy |
StackTreeDepth-First Search |
| 23 |
Binary Tree Preorder Traversal |
Easy |
StackTreeDepth-First Search |
| 24 |
Binary Tree Pruning |
Medium |
TreeDepth-First SearchBinary Tree |
| 25 |
Binary Tree Right Side View |
Medium |
TreeDepth-First SearchBreadth-First Search |
| 26 |
Binary Tree Tilt |
Easy |
TreeDepth-First SearchBinary Tree |
| 27 |
Binary Tree Upside Down |
Medium |
TreeDepth-First SearchBinary Tree |
| 28 |
Binary Tree Vertical Order Traversal |
Medium |
Hash TableTreeDepth-First Search |
| 29 |
Binary Tree Zigzag Level Order Traversal |
Medium |
TreeBreadth-First SearchBinary Tree |
| 30 |
Boundary of Binary Tree |
Medium |
TreeDepth-First SearchBinary Tree |