Find mode or minimum with time-space tradeoffs
Company: Meta
Role: Software Engineer
Category: Coding & Algorithms
Difficulty: medium
Interview Round: Technical Screen
For an unsorted array of integers, implement two functions:
(
1) return the minimum value;
(
2) return the value that appears most frequently (the mode). For the mode, compare a sorting-based approach with a hash-map counting approach, and, if the value range is known and small, a counting-array approach. Discuss the time–space tradeoffs, how to reduce runtime by using more space, and how your choices change under streaming input or strict memory limits.
Overview: This question evaluates algorithm design and analysis skills—particularly time–space tradeoffs, frequency counting techniques (sorting, hashing, and counting arrays), and handling streaming or memory-constrained inputs in the Coding & Algorithms domain.