Germ spread

Chef wants to cultivate his favorite crop. Bob also being a lover of this crop, asked Chef for some, but Chef denied since he is a selfish person and only thinks about himself. Bob wants to take revenge and has decided to put germs in his field and destroy all his crops. Let's denote this special crop by $c$. Given a field of $N$ X $M$, $c$ are placed at arbitrary locations, and the leftover p