Hash maps and sets
Comes up in: DSA
This concept is being written. It gets the full five steps — explanation, predict, interview angle, practice with tests, and review cards. Here is exactly what it will cover, so you can study it elsewhere in the meantime.
What it covers
- hashing idea
- collisions (chaining, open addressing)
- average O(1)
- frequency counting
- Map vs object keys
Words you will know
What you will practise
- implement a simple hash map with chaining
Interview questions this answers
- How does a hash map achieve O(1) average lookups? What is the worst case?