Hashing
Hash maps and sets — O(1) average lookups that turn "search every item" into "ask directly".
This topic is part of Pro.
Free covers the C and Python courses, the first three DSA topics, the opening system design lessons and the beginner AI lessons, all with the full coach. Pro opens the rest of the library in the FollowtheDamnCode app.
What is in it
- 1How hash tables workHash functions, buckets, collisions, and the resizing that keeps lookups O(1) on average. Pro
- 2Sets and maps in practiceHave I seen it, how many, and where was it — the three questions that cover most hashing code. Pro
- 3The complement pattern (Two Sum)Instead of searching for a partner, remember what you've seen and ask for exactly the partner you need. Pro
- 4Choosing the right keyGroup things that "belong together" by computing a key they all share. Pro