Project 3: Emergency Room Patient Scheduling

Note: While you are only allowed to work within your group on this assignment, with respect to the use of data structures within the C++ STL please feel free to share and discuss examples of code that utilizes these data structures. Do not, however, share nor discuss code pertaining to solving the challenge in the assignment.

In this project, you will utilize some of the data structures we have discussed in this class to create a log of patients in an emergency room. There are no training wheels for this project. You have 100% of control over your program and thus must properly read in the input, and produce the expected output.

Goals for this project

By the time you have completed this project, you should:

  • be comfortable parsing data from an input stream
  • know which data structure to use for a particular task (the right tool for the job)
  • be able to use data structures contained within the C++ standard template library

Project description

The program you write, main.cpp, will be provided structured input to the standard input stream (see the input section below) that describes a number of symptoms, the doctors available, and the times that patients arrive on a single day at hospital’s emergency room. You will output to the standard output stream a log file (see the output section below) containing the events as they occured that day.


Below is an example of what the input format will look like. Notice that there are three distinct sections to the file: priorities, doctors, and patient arrivals.

# Priorities
01 Cough
05 Head Ache
08 Bleeding
10 Decompression Sickness
# Doctors
Dr. Something Orother
# Patient Arrivals
09:11 "Vincent van Gogh" "Bleeding" 150
09:30 "Phineas Gage" "Head Ache" 65
09:45 "Neil Armstrong" "Decompression Sickness" 360

Priorities section

Each line within the first section can be broken into TWO_DIGIT_NUM space SYMPTOM where TWO_DIGIT_NUM represents the priority from 00 to 99, and SYMPTOM is the description of the symptom. Higher values indicate higher priority, and the symptom can contain multiple words (it should be everything after the separating space). You will want to map each symptom to its priority so that you can easily look up a symptom’s priority by its name.

Doctors section

Each line within the second section only contains a doctor’s name. All characters on the line (up to the newline) should be considered part of the name. Doctors should be added to a queue in the order that they are listed.

Patient arrivals section

Each line within the third section can be broken into ARRIVAL_HOUR colon ARRIVAL_MINUTE space quote PATIENT_NAME quote space quote SYMPTOM quote VISIT_DURATION.

ARRIVAL_HOUR is a number between 00 and 23. ARRIVAL_MINUTE is a number between 00 and 59. These two values combined make up the time of the event. All the events (lines) will be given in sequential order and will all occur between 00:00 and 23:59.

PATIENT_NAME is the name of the patient and should be everything contained between the two double-quote characters ("). Likewise, SYMPTOM is everything between the second set of double-quote characters.

Finally, VISIT_DURATION specifies the amount of time in minutes this patient spends with the doctor when visted by the doctor.


Below is an example of what the output needs look like when given the above input. Notice that there is one line per event.

09:11 Vincent van Gogh arrives
09:11 Dr. Something Orother visits Vincent van Gogh about Bleeding
09:30 Phineas Gage arrives
09:45 Neil Armstrong arrives
11:41 Vincent van Gogh departs
11:41 Dr. Something Orother visits Neil Armstrong about Decompression Sickness
17:41 Neil Armstrong departs
17:41 Dr. Something Orother visist Phineas Gage about Head Ache
18:46 Phineas Gage departs

Output should be produced in the order that events occur. Here a few rules:

  • When multiple events occur at the same time arrivals should be output first, followed by departures, and finally visits.
  • When multiple arrivals occur at the same time they should be output in the same order as they appear on the input stream.
  • When multiple departures occur at the same time, they should be output in the same order that their arrivals occured.

Finally, multiple visits can only occur at the same time if there are more than one available doctor. The patient with the highest priority symptom should be scheduled the doctor who least-recently finished visiting a patient. Additionally:

  • Doctors who have yet to visit a patient should be assigned patients in their input order (they have priority over doctors who have visited a patient)
  • When multiple patients have symptoms of equal priority, whoever arrived first should be scheduled first.
  • When multiple patients with equal priority who arrived at the same time are waiting, they should be visited in the same order that their arrivals occured.
  • If there are patients and no doctors available, the output should simply be “No doctors available!n”

Project preparation

For this assignment, you actually do not need any files. However, to make things somewhat simpler, I have provided a MaxHeap class in the file heap.h. While you will not submit heap.h this file will be available on the submission system should you wish to use it.

To begin create a proj3 directory (assuming you haven’t already done so):

mkdir -p cs24/proj3

Change the permissions of the cs24 directory such that only your account can access the files inside this directory. This step is incredibly important. If omitted, other students can peek at your work and you may be held partially responsible. It should also go without saying that you may not give other students access to your account. If you’ve done that in the past please change your password at this time.

chmod 700 cs24

Change into the proj3 directory and copy the files you will need for this project:

cd cs24/proj3
cp ~bboe/public_html/cs24_f13/code/proj3/* .

Working with project 3

You will only submit main.cpp thus put all of your code in this program. You will very likely want to utilize the queue and unordered_map libraries from the STL, and the MaxHeap class from heap.h.

When you’re ready to build and test your program run:


And run your program via:



To make testing simpler you may want to make test files and then use input redirection to provide the test file as the standard input to your program. For instance if you want to run your program against sample_input.txt you can run one of the following:

./er < sample_input.txt
cat sample_input.txt | ./er

Submitting the assignment

Only one person in a group need submit the assignment but make sure that both you and your partner can view the submission on the submission site. If you cannot, you need to complete the making a group process. Please review the submission instructions as needed. Note that you may resubmit this assignment as many times as necessary up until the deadline.


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