Find value on most distinct levels
Company: IXL Learning
Role: Software Engineer
Category: Coding & Algorithms
Difficulty: Medium
Interview Round: Technical Screen
Given a binary tree whose nodes store values (e.g., characters), find the value that appears on the greatest number of distinct depth levels. For example, for the tree:
A
/ \
A B
/ \
C C
the answer is 'A' because it appears on two different levels (levels 1 and
2). Describe an algorithm, justify its correctness, and analyze its time and space complexity.
Quick Answer: This question evaluates a candidate's understanding of binary tree structures, level-wise aggregation and frequency analysis, along with algorithm design and complexity reasoning.