Language/Platform

This project must target a Unix platform and execute properly on our cs1 or csgrads1 Linux server.

The project must be written in C, C++, or Java.

If using C or C++, you must use POSIX pthreads and semaphores.

If using Java, you must use Java Threads and Java Semaphores (java.util.concurrent.Semaphore). 

You should not use the synchronized keyword in Java.

You should not use any Java classes that have built-in mutual exclusion.

Any mechanisms for thread coordination other than the semaphore are not allowed.

Doctors Office Simulation

This project will simulate a visit to the doctors office. It is similar to the barbershop example in the textbook.

Overview

The clinic to be simulated has doctors, each of which has their own nurse. Each doctor has an office of his or her own in which to visit patients. Patients will enter the clinic to see a doctor, which should be randomly assigned. Initially, a patient enters the waiting room and waits to register with the receptionist. Once registered, the patient sits in the waiting room until the nurse calls. The receptionist lets the nurse know a patient is waiting. The nurse directs the patient to the doctors office and tells the doctor that a patient is waiting. The doctor visits the patient and listens to the patients symptoms. The doctor advises the patient on the action to take. The patient then leaves.

Threads

Receptionist one thread

Doctor one thread each, maximum of 3 doctors

Nurse one per doctor thread, identifier of doctor and corresponding nurse should match

Patient one thread each, up to 30 patients

Inputs

The program should receive the number of doctors and patients as command-line inputs.

Other rules:

A thread should sleep 1 second at each step the thread prints an activity.

All mutual exclusion and coordination must be achieved with semaphores.

A thread may not use sleeping as a means of coordination.

Busy waiting (polling) is not allowed.

Mutual exclusion should be kept to a minimum to allow the most concurrency.

Each thread should only print its own activities. The patient threads prints patient actions and the doctor threads prints doctor actions, etc.

Your output must include the same information and the same set of steps as the sample output.

Output

Each step of each task of each thread should be printed to the screen with identifying numbers so it is clear which threads are involved.

Begin by printing the number of patients, nurses, and doctors in this run.

Thread activity output sample. Your output should contain the same set of steps per thread:

Run with 3 patients, 3 nurses, 3 doctors

Patient 0 enters waiting room, waits for receptionist

Receptionist registers patient 0

Patient 0 leaves receptionist and sits in waiting room

Patient 2 enters waiting room, waits for receptionist

Nurse 0 takes patient 0 to doctor's office

Receptionist registers patient 2

Patient 0 enters doctor 0's office

Patient 2 leaves receptionist and sits in waiting room

Patient 1 enters waiting room, waits for receptionist

Nurse 2 takes patient 2 to doctor's office

Receptionist registers patient 1

Patient 2 enters doctor 2's office

Doctor 0 listens to symptoms from patient 0

Patient 1 leaves receptionist and sits in waiting room

Patient 0 receives advice from doctor 0

Doctor 2 listens to symptoms from patient 2

Patient 2 receives advice from doctor 2

Nurse 1 takes patient 1 to doctor's office

Patient 1 enters doctor 1's office

Doctor 1 listens to symptoms from patient 1

Patient 1 receives advice from doctor 1

Patient 0 leaves

Patient 2 leaves

Patient 1 leaves

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