School assignments that count: simulating the COVID outbreak with the C language

Giulia got an exciting assignment from her teacher: Write a C program that simulates (a simplified version of) COVID outbreak spreading across a population of 200 people. When a healthy person comes into contact with a sick person, the healthy person becomes ill, too. After some time, a sick person will recover. A recovered person cannot infect a healthy person nor become sick again after coming in contact with a sick person. »