Question
You climb a staircase of n steps using moves of 1 or 2 steps. A 2-step move is tiring, so you may never make two 2-step moves in a row — every 2-step must be followed by a 1-step (or be the final move). Return the number of distinct move sequences that end exactly on step n. For n = 0 return 1. For example, n = 4 has 4 sequences: 1111, 112, 121, 211 (22 is forbidden).
count_paced_climbs(n: int) → int[4]out4[5]out6State 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.
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.