Foundations
The do-not-skip prerequisites. Big-O, recursion, bit ops, math for interviews, language idioms. Most readers want to skip Part 0 and shouldn't.
- Chapters
- 7
- Hours
- 2
- Difficulty
- Beginner
- 0.0beginner
How to use this handbook
How to read this handbook: who it's for, what to skip, how to pick a language, and the four questions every DSA resource ducks.
- 0.1beginner
Computational complexity and Big-O
Computational complexity, Big-O, and the asymptotic vocabulary every algorithm chapter assumes you have. The five Bachmann-Landau notations.
- 0.2beginner
The recursion mental model
The mental model for recursion: base case, recursive case, and how to read tree-shaped recursion without losing your place.
- 0.3beginner
Bit manipulation primer
Bit manipulation primer: AND, OR, XOR, NOT, shifts, popcount. The bit-level idioms that show up in interview problems.
- 0.4beginner
Math for interviews
The math you actually need for technical interviews: modular arithmetic, GCD, primality, combinatorics, integer overflow.
- 0.5beginner
Language idioms across Python, Java, C++, Go
Idiomatic patterns for Python, Java, C++, and Go: collections, iteration, sorting, comparators. The dialect each language wants you to write.
- 0.6beginner
Choosing your interview language
How to pick a language for technical interviews: trade-offs, what each language costs you in problem-solving time, and a decision tree.