| 230 | Kth Smallest Element in a BST | Medium |
| 501 | Find Mode in Binary Search Tree | Easy |
| 513 | Find Bottom Left Tree Value | Medium |
| 515 | Find Largest Value in Each Tree Row | Medium |
| 543 | Diameter of Binary Tree | Easy |
| 606 | Construct String from Binary Tree | Easy |
| 654 | Maximum Binary Tree | Medium |
| 863 | All Nodes Distance K in Binary Tree | Medium |
| 872 | Leaf-Similar Trees | Easy |
| 894 | All Possible Full Binary Trees | Medium |
| 938 | Range Sum of BST | Easy |
| 998 | Maximum Binary Tree II | Medium |
| 1026 | Maximum Difference Between Node and Ancestor | Medium |
| 1361 | Validate Binary Tree Nodes | Medium |
| 1457 | Pseudo-Palindromic Paths in a Binary Tree | Medium |
| 1609 | Even Odd Tree | Medium |
| 2196 | Create Binary Tree From Descriptions | Medium |
| 2265 | Count Nodes Equal to Average of Subtree | Medium |
| 2385 | Amount of Time for Binary Tree to Be Infected | Medium |