Vertical Column Sums in Binary Tree | Dataford Interview Questions

At Meta, a tree-shaped structure may need to be aggregated by vertical alignment rather than by level. Given the root of a binary tree, return the sum of node values in each vertical column from leftmost column to rightmost column.

A node's column index is defined relative to the root:

The root is in column 0
The left child of a node in column c is in column c - 1
The right child of a node in column c is in column c + 1

Formal Specification

Implement a function:

Input: root, the root node of a binary tree, represented as nested dictionaries or objects with fields val, left, and right, or null for an empty tree
Output: A list of integers where each value is the sum of one vertical column, ordered from the smallest column index to the largest

Constraints

0 <= number of nodes <= 10^5
-10^4 <= node.val <= 10^4
root may be null
The tree can be skewed or balanced

Function Signature

def vertical_column_sums(root):

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