Level Order Traversal of Binary Tree

An algorithm to process all the nodes in a tree by levels. It starts from the root node and visits all nodes at level 1, followed by all nodes at level 2, and so on.

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Given a binary tree, the task is to print level order traversal line by line of the tree.

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This method involves using 2 functions: one to print all nodes at a specific level (CurrentLevel), & another to print level order traversal of the tree (Levelorder).

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Time complexity: O(n^2) for a skewed tree. Space complexity: O(n) for a skewed tree, & for a balanced tree, the call stack uses O(log n) space.

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1. Insert root into queue, & iterate over it until queue is empty. 2. In every iteration, pop from top of queue & print the value at top of queue. 3. Add left & right nodes to end of queue.

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Time Complexity: O(N) where n is no. of nodes in the binary tree. Space Complexity: O(N) where n is no. nodes in the binary tree.

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Start your journey now and learn how to perform level order traversal of binary tree using different approaches.

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Level Order Traversal of Binary Tree

A Popular Method for Traversing Tree Data Structure

An algorithm to process all the nodes in a tree by levels. It starts from the root node and visits all nodes at level 1, followed by all nodes at level 2, and so on.

What is Level Order Traversal?

Given a binary tree, the task is to print level order traversal line by line of the tree.

Problem Statement

This method involves using 2 functions: one to print all nodes at a specific level (CurrentLevel), & another to print level order traversal of the tree (Levelorder).

Approach 1: Recursive Approach

Time complexity: O(n^2) for a skewed tree. Space complexity: O(n) for a skewed tree, & for a balanced tree, the call stack uses O(log n) space.

1. Insert root into queue, & iterate over it until queue is empty. 2. In every iteration, pop from top of queue & print the value at top of queue. 3. Add left & right nodes to end of queue.

Approach 2: Using Queue

Time Complexity: O(N) where n is no. of nodes in the binary tree. Space Complexity: O(N) where n is no. nodes in the binary tree.

Start your journey now and learn how to perform level order traversal of binary tree using different approaches.

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