DSA Tracker

Brute-force: recursion O(2^n) — two branches per step

Optimal: DP or two variables O(n) O(1) space

Brute-force: try all combinations O(S^n) recursion

Optimal: bottom-up DP table O(S·n) where S=amount, n=coins

Brute-force: try rob/skip every house O(2^n)

Optimal: DP with two variables O(n) O(1) space

Brute-force: check all subsequences O(2^n)

DP: O(n²) table, Optimal: O(n log n) with binary search

Brute-force: try every partition O(2^n)

Optimal: DP with word set O(n²) or O(n·m)

Brute-force: try all buy/sell with cooldown O(2^n)

Optimal: state machine DP O(n) — hold/sold/rest

Week 17: Graphs & Dynamic Programming