Question
Given a non-empty list of integers, find the value that occurs the fewest times. If several values tie for the lowest occurrence count, return the numerically smallest of them, making the answer deterministic. For example, in [4, 4, 7, 7, 7, 2, 2] both 4 and 2 occur twice while 7 occurs three times, so the rarest values are 4 and 2 and the answer is 2. A single value list returns that value.
rarest_value(nums: list[int]) → int[[4,4,7,7,7,2,2]]out2State 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.