| ID | Title | Difficulty |
|---|---|---|
| 2509 | Cycle Length Queries in a Tree | Hard |
| 2641 | Cousins in Binary Tree II | Medium |
| 2673 | Make Costs of Paths Equal in a Binary Tree | Medium |
| ID | Title | Difficulty |
|---|---|---|
| 2509 | Cycle Length Queries in a Tree | Hard |
| 2641 | Cousins in Binary Tree II | Medium |
| 2673 | Make Costs of Paths Equal in a Binary Tree | Medium |