Solution: Vertical Order Traversal of a Binary Tree

Explore the vertical order traversal of a binary tree by applying breadth-first search (BFS). Understand how to maintain column indices, use a hash map for node storage, and achieve level-wise traversal. Learn the approach's time complexity is O(n) and space complexity is O(n), allowing you to efficiently solve this common tree traversal problem.

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Statement
Solution
- Naive approach
- Optimized approach using tree breadth-first search

Statement

Find the vertical order traversal of a binary tree when the root of the binary tree is given. In other words, return the values of the nodes from top to bottom in each column, column by column from left to right. If there is more than one node in the same column and row, return the values from left to right.

Constraints:

The number of nodes in the tree is in the range [1, 500].
$0 \leq$ Node.data $\leq 1000$

Solution

So far, you’ve probably brainstormed some approaches and have an idea of how to solve this problem. Let’s explore some of these ...