Missing order items
A warehouse checks deliveries against purchase orders. You get the list of item codes that were ordered and the list of codes actually received; both can repeat, and quantities matter — ordering code 4 twice but receiving it once means one unit of 4 is missing. Return every missing unit as a list of codes in ascending order (with repeats). Extra received units are ignored. Example: ordered [4, 4, 7, 9], received [4, 9] gives [4, 7].
Implement
missing_items(ordered: list[int], received: list[int]) → list[int]Examples
in
[[4,4,7,9],[4,9]]out[4,7]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 15 min
solution.py
InputExpectedGot
[[4,4,7,9],[4,9]][4,7]not run yetsample