What is a 'Perfect Hash Function'?

What is a 'Perfect Hash Function'?

Approach: Define a hash function with zero collisions for a fixed set of keys.

A hash function that maps each element of a specific, fixed set of keys to a unique integer, resulting in zero collisions. Useful for static datasets where the keys are known in advance.

Follow-up: What is a 'minimal' perfect hash function?

Key concepts: static keys, O(1) lookup, collision-free.