Iterative Post-Order Traversal of Binary Tree in C++
Due to the recursive nature of the problem, it is easy and efficient to implement the post order traversal using recursion. But we can also implement it using loops.
Algorithm for Iterative Post-Order Binary Tree Traversal in C++
The iterative approach uses a stack to simulate the recursive behavior.
- Push the root node to the stack.
- Initialize a temporary pointer to track the previously visited node.
- Loop until the stack is empty:
- Peek at the top node on the stack.
- If the top node has no children or the previously visited node is its right child, visit the top node and pop it off the stack.
- Otherwise:
- If the top node has a right child and it hasn’t been visited yet, push the right child onto the stack.
- If the top node has a left child and it hasn’t been visited yet, push the left child onto the stack.
- After the loop completes, all nodes will have been visited in post-order.
Postorder Traversal of Binary Tree in C++
Post-order binary tree traversal is a type of depth-first traversal that follows the order of visiting the left subtree, then the right subtree, and finally the node itself. It is useful for operations where you need to work with a node only after you’ve dealt with its children, such as when calculating the size of the tree or deleting the tree.
In this article, we will learn about post-order binary tree traversal in C++, how to implement it in C++ using both recursion and iteration methods and analyze the time and space complexity of both methods.