Contamination spread time
A grid models a warehouse where each cell is 0 (empty), 1 (a healthy unit), or 2 (a contaminated unit). Every minute, each contaminated unit spreads to its orthogonally adjacent healthy units, contaminating them. Return the minimum number of minutes until no healthy unit remains, or -1 if some healthy unit can never be reached. If there are no healthy units initially, return 0.
Implement
spread_time(grid: list[list[int]]) → intExamples
in
[[[2,1,1],[1,1,0],[0,1,1]]]out4What 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 25 min
solution.py
InputExpectedGot
[[[2,1,1],[1,1,0],[0,1,1]]]4not run yetsample