In a doctor$$s chamber potential patients need to follow $2$ steps in order to consult

the doctor. First, they have to take a serial over the phone. If they get serials then the first $20$

patients of the serial get called for the consultation. After getting called, patients need to

maintain a queue of $5$ pupils according to their serials and others need to wait. Once a patient

gets called by the doctor, a patient from waiting can join in the queue according to the serial.

Logically explain which functions from operating systems structure have similarities with the

above scenario?