Code Room
CodingHard
Question
Implement a FreqStack: push(x) adds a value; pop() removes and returns the most frequent value, breaking ties by the one pushed most recently (closest to top). Simulate a sequence of operations: each op is ['push', x] or ['pop']. Return the list of values returned by each 'pop'.
Implement
freq_stack(ops: list[list]) → list[int]Examples
in
[[["push",5],["push",7],["push",5],["push",7],["push",4],["push",5],["pop"],["pop"],["pop"],["pop"]]]out[5,7,5,4]What a strong answer looks like
State your approach and its time/space complexity out loud before you optimize. Handle the edge cases (empty input, duplicates, overflow), and say why you chose this over the brute force. Green tests are the floor, not the grade.
Learn the concepts
Vibe coding: describe the solution in plain language (or narrate it) and the coach grades your approach. Generating runnable code from your description is coming next.
Run or narrate your approach, then ask the coach.