I will list down some problems on the topic of trees and graphs that are commonly asked in interviews. Please revise topics on tress such as Binary Trees, Binary Search Tree (BST), Balancing a Tree, Full and Complete Trees, Binary Tree Traversals...
Trees and Graphs
Postorder Traversal Without Using Recursion With Two Stacks.
Postorder Traversal Without Using Recursion With One Stack
Check if a Binary Tree is a Binary Search Tree (BST) using Inorder Traversal.