Types: m: int, n: int, existing_stores: List[Tuple[int, int]], candidate_locations: List[Tuple[int, int]]
Ranges: 1 ≤ m, n ≤ 100, (1 ≤ x, y ≤ m, n) for coordinates in existing_stores and candidate_locations
Addtl Info: End of input is indicated by a line containing a single zero.