hw1, Notifications. Due date: Monday 9/26 10 a.m.

(Early deadline: Friday 1pm with +7 extra points, email instructor 1/2 hour before the dealine if you choose this option).

You will create a C++ program that will combine notifications (using linked lists). There are many notifications in a text file. Each notification includes the person to which an email to which is sent to, a subject, and a message. The notifications need to be combined to make more efficient both the sending, and the actions by the person receiving them.

Input

The input is one or more plain-text files. In any input file, each line is terminated with an end-of-line character. Each line will have a fixed set of data, separated by the tab character (that is, \t). Lines that start with the symbol # should be considered comments and therefore skipped. There may be empty lines in the input file; such lines should be skipped.

Example 1:

Meredith   Invoice  PARK-1203
Jackson    Approve-reservation  7634
Amelia     Approve-reservation  7658
Jackson    Invoice  DISC-7303
Callie     Approve-travel    TR-N208-TX
Arizona    Invoice  DISC-7304(Cancelled)
# this line is a comment because it starts with #
Owen       Approve-purchase-order  D-9076
Miranda    Purchase-order-revise   D-9076
Arizona    Invoice  DISC-7304(Cancelled)
Meredith   Invoice  PARK-1205
Cristina   Invoice  TECH-3030
Owen       Approve-purchase-order  D-9077
Callie     Invoice    DISC-7294
Callie     Invoice    DISC-7294
Amelia     Approve-reservation  7664
Callie     Invoice    DISC-7294
Cristina   Invoice  TECH-2980(Cancelled)
Jackson    Invoice  DISC-7343
Callie     Approve-travel    TR-N209-TX
Meredith   Invoice  TECH-3034
Owen       Approve-purchase-order  D-9078
Amelia     Approve-reservation  7669
Miranda    Purchase-order-cancellation   D-9076
Amelia     Approve-reservation(Cancelled)  7669
Callie     Review-invoice    DISC-7304

Each line that is not a comment (or empty line) will always have three items. The first is the person receiving the notification. The second item is the subject line of the email. The third is the 'body' of the email message.

For the purpose of the assignment, we will pretend that another part of a notification system will replace the name for the actual email, and there will be a nicely formatted email message created automatically from the other information of each line.

Program specification

The main program should be called notify and the syntax in which it will be tested is as follows:

./notify "input=FILENAME"

The parameter input specifies the name of the input file.

Example of program calls:

./notify "input=uh-gray.1.txt"

The source code will be compiled as follows:

g++ -std=c++11 -o notify -I ./ *.cpp

Rules to combine notifications:

1. When the same person is going to receive more than one email having the same subject, then the contents of the message need to be combined (separated by commas) into only one notification.

Actually the combined messages are separated by a comma and a space, such as ", "

In the example input, there are 3 notifications for "Meredith" with the subject "Invoice", and with different message. The notifications will be combined into one: Meredith Invoice PARK-1203, PARK-1205, TECH-3034

The order matters. If it is done in an order different to that in which the notifications appear, then the program may fail test cases.

2. Duplicate notifications may happen and they need to be combined into one. See example of Callie Invoice DISC-7294

3. First special case: Any notification Approve-reservation that is followed (either immediately or after one or more lines) by a corresponding Approve-reservation(Cancelled) will require that both notifications be eliminated. See example of Amelia Approve-reservation 7669. The "message" has to match, and the "person" has to match.

4. Second special case: Any notification Approve-purchase-order that is followed (either immediately or after one or more lines) by a corresponding Purchase-order-cancellation will require that the first notification be eliminated. See example of Miranda Purchase-order-cancellation D-9076. The "message" has to match, but the "person" does not have to match (such as Owen in this example). Any intermediate notification Purchase-order-revise with a matching "message" also needs to be eliminated (regardless of whether "person" was a match).

Rules to combine input files:

1. The input file will always have the substring .1.txt (as the last part of the filename), which is used to attempt to open the next file, file 2, if it exists. Then the program will open file 3, if it exists, and so on up to and including file 9 (if it exists).

In the example listed, the input file name uh-gray.1.txt is file 1. File 2 would be: uh-gray.2.txt, which is not explicitly specified to your program. Instead, your program needs to determine whether file 2 exists, and if so, open it and process it. When your program does not find file k, then it does not have to keep looking for file k + 1

2. Each input file is to be processed independently of the other input files (if any). That is, the notifications of each input file are combined for that input file independently of other input files (if any).

3. Global list of all input files: Once every input file has had its notifications combined (independently of the other input files), a global list of notifications will be created by taking one notification at a time of each of the input files.

Example:

File 1 has notifications A B C D

File 2 has notifications G H K

File 3 has notifications M N

File 4 has notifications Q R T S

The global list would be: A G M Q B H N R C K T D S

4. The final step is to combine the global list of notifications. For example, if file 1 has a notification Alex Invoice PEDS-765, and file 4 has a notification Alex Invoice PSYCH-3654, then such notifications need to be combined into only one notification: Alex Invoice PEDS-765, PSYCH-3654

Output

Your program will output to the console (such as via cout) with the results of combining notifications. Your program must follow the output format exactly to facilitate automated grading (and to avoid failing test cases due to things such as output of an empty line at the end).

Output for the input example 1.

Meredith   Invoice  PARK-1203, PARK-1205, TECH-3034
Jackson    Approve-reservation  7634
Amelia     Approve-reservation  7658, 7664
Jackson    Invoice  DISC-7303, DISC-7343
Callie     Approve-travel    TR-N208-TX, TR-N209-TX
Arizona    Invoice  DISC-7304(Cancelled)
Cristina   Invoice  TECH-3030, TECH-2980(Cancelled)
Owen       Approve-purchase-order  D-9077, D-9078
Callie     Invoice    DISC-7294
Miranda    Purchase-order-cancellation   D-9076
Callie     Review-invoice    DISC-7304

Example of how to output each line:

cout << person << "\t" << subject << "\t" << message << endl;

The output of your program should not have empty lines or comments.

Assumptions

• Each input file can fit in main memory (not larger than 10kb).

Requirements

• Must utilize linked-lists to do the combining of operations (either within a file, or when combining various files into a single list of notifications). Failure to do so will result in a grade of 2 points (out of 100).
• Place your codes in a folder in your home directory, named: hw1 (Failure to do so will cause your program to have a zero grade due to inability for doing automated grading).
• Your program should not produce any unexpected output when it is doing intermediate calculations because doing so will interfere with automated grading and some test cases will fail.
• You can not assume a maximum number of lines in the input file.

Miscellaneous

• A good explanation on how to use c++ parameters from the command-line