juniorHash Tables
How does a simple modulo hash work?
Updated Apr 28, 2026
Short answer
index = key % table_size.
Deep explanation
Hash tables are fundamental for fast lookups. index = key % table_size. By using a mathematical transformation, they bypass linear scanning required by arrays.
Real-world example
A dictionary or phonebook lookup.
Common mistakes
- Assuming hash tables are always O(1) without considering collision frequency.
Follow-up questions
- What happens if the table is too full?