Map indices between lists
A quiz app shuffled its question ids. You have the original order in list a and the shuffled order in list b; both lists contain exactly the same distinct integers, just arranged differently. For each position i of a, find where that id landed in b, and return the list r with r[i] equal to the index of a[i] within b. For example, a = [12, 28, 46] and b = [46, 12, 28] give [1, 2, 0]. Avoid searching b repeatedly — one preprocessing pass should make every lookup O(1).
Implement
position_map(a: list[int], b: list[int]) → list[int]Examples
in
[[12,28,46],[46,12,28]]out[1,2,0]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.
0:00 of about 10 min
solution.py
InputExpectedGot
[[12,28,46],[46,12,28]][1,2,0]not run yetsample