Change Log

We may make minor changes to the spec to address/clarify some outstanding issues. These may

require minimal changes in your design/code, if at all . Students are strongly encouraged to check the

change log regularly.

Version 1: Released on 20 October 2023

Objectives

The assignment aims to give you more independent, self-directed practice with

· advanced data structures, especially graphs

· graph algorithms

· asymptotic runtime analysis

Admin

Marks 3 marks for stage 1 (correctness)

5 marks for stage 2 (correctness)

2 marks for stage 3 (correctness)

1 mark for complexity analysis

1 mark for style

Total: 12 marks

Due          5:00:00pm on Monday 13 November (week 10)

Late 5% penalty per day late

(e.g. if you are 25 hours late, your mark will be reduced by 10%)

Aim

The objective is to write a program tripView. c that generates an optimal trip on (a part of) Sydney's

railway network based on user preferences.

Input

Railway stations

The first input to your program consists of an integer n > 0, indicating the number of railway stations on

the network, followed by n*2 lines of the form:

railway-station

transfer-time

where the first line is the name of a station and the second line denotes the time - in minutes -it takes to transfer to a different train at that station.

Here is an example:

prompt$./tripView

HarrisPark

TownHall

3

NorthSydney

2

You may assume that:

· The  input  is  syntactically  correct.

· The  maximum  length(strlen())  of  the  name  of  a  railway  station  is  16  and  will  not  use  any

spaces.

· The transfer time will be a positive integer.

·No name will be input more than once.

Hint:

To read a single line with a station name you should use:

scanf("%s",name);

where name is a string, i.e. an array of chars.

Timetables

The next input to your program is an integer m >0, indicating the number of trains on any day, followed by m timetables. Each timetable starts with the number s >1 of stops followed by s*2 lines of the form:

station hhmm

meaning that you can get on or off the train at that station at the given time (hh - hour, mm-minute).

Here is an example:

Number of timetables:  2

Number    of    stops:    3

HarrisPark

0945

TownHall

1020

NorthSydney

1035

Number  of  stops:  2

TownHall

1024

NorthSydney

1033

You may assume that:

· The  input  is  syntactically  correct.

· All  times  are  given  as  4  digits  and  are  valid,  ranging  from  0000  to  2359.

· Only train stations that have been input earlier as part of the network will be used. · The stops are input in the correct temporal order.

· All trains reach their final stop before midnight.

Trip View

The final input to your program are user queries:

From: HarrisPark

To: NorthSydney

Arrive at or before:  1200

As before, you may assume that the input is corect: Two different valid railway stations followed by a valid time in the form of 4 digits.

Your program should terminate when the user enters "done" when prompted with From:

From: done Bye prompt

Stage 1 (3 marks)

Stage 1 requires you to generate a suitable data structure from the input.

Test cases for this stage will only use queries FromStation, ToStation, ArrivalTime such that:

· there exists one, and only one, train that travels from FromStation      to      ToStation;

· this train arrives on, or before, the given ArrivalTime ; and

·this train is the desired output for the query.

Therefore, at this stage all you need to do is find and output the connection between the two train stations, including all the stops along the way and the arrival/departure times.

Here is an example to demonstrate the expected behaviour of your program for a stage 1 test:

prompt$./tripView

Size  of  network:  7

Ashfield

5

Central

8

HarrisPark

1

MilsonsPoint

2

NorthSydney

2

Redfern

5

TownHall

3

Number of timetables:  2

Number   of   stops:   5

HarrisPark

0945

Ashfield

0955

Redfern

1006

TownHall

1020

NorthSydney

1035

Number   of   stops:   4

Redfern

1359

Central

1406

TownHall

1410

MilsonsPoint

1430

From: Central

To:  MilsonsPoint

Arrive  at  or before:  1600

1406 Central

1410 TownHall

1430 MilsonsPoint

From: Ashfield

To: NorthSydney

Arrive  at  or before:  1040

0955 Ashfield

1006 Redfern

1020 TownHall

1035 NorthSydney

From:      done

Bye

prompt

COMP902423T3 -Assignment

Stage  2  (5  marks)

For the next stage, your program should find and output a connection from FromStation to ToStation that:

· may involve one or more train changes;

· arrives at ToStation no later than ArrivalTime; and

· leaves as late as possible.

Note that you can get onto a different train at any station, but it is necessary to take into account the time it takes to change trains at that station.

In all test scenarios for this stage there will be at most one connection that satisfies all requirements.

Here is an example to demonstrate the expected behaviour of your program for stage 2:

prompt$./tripView

Size of network:  6

Ashfield

5

Central

8

HarrisPark

N1orthSydney

2

Redfern

5

TownHall

3

Number of timetables:  2

Number of stops: 5

HarrisPark

0945

Ashfield

0955

Redfern

1006

TownHall

1020

NorthSydney

1035

Number     of    stops:     3

HarrisPark

0950

Central

1010

TownHall

1017

From: HarrisPark

To: NorthSydney

Arrive at or before:  1040

0950 HarrisPark

1010 Central

1017 TownHall

Change  at  TownHall

1020 TownHall

1035  NorthSydney

From:      done

Bye

prompts

If there is no connection that satisfies the requirements, then the output should be: No connection.

From: HarrisPark

To:   TownHall

Arrive by: 1015

No connection.

Stage 3 (2 marks)

For the final stage, if there are multiple possible connections with the same latest departure time, your program should take into account the additional user preference that:

· among all the connections with the latest possible departure time, choose the one with the

shortest overall travel time.

You may assume that there will never be more than one connection with the latest possible departure  time and the shortest overall travel time. Note also that travel time includes the time it takes to change trains and the waiting time if applicable.

Here is an example to demonstrate the expected behaviour of your program for stage 3:

prompt$./tripView

Size of network: 3

HarrisPark

1

NorthSydney

2

TownHal1

3

Number of timetables:  2

Number   of   stops:   3

HarrisPark

0945

TownHall

1020

1035

Number   of   stops: 2

TownHall

1024

NorthSydney

1033

From: HarrisPark

To:  NorthSydney

Arrive  at  or  before:  1040

0945  HarrisPark

1020  TownHal1

Change   at   TownHall

1024  TownHall

1033   NorthSydney

From:       done

Bye

prompts

Complexity Analysis(1 mark)

You should include a time complexity analysis for the asymptotic worst-case running time of your program, in Big-Oh notation, depending on the size of the input:

1.the size of the network,n

2. the number of timetables,m

3. the maximum number of stops on any one timetable, s.

Hints

If you find any of the following ADTs from the lectures useful, then you can, and indeed are encouraged

to, use them with your program:

·  linked  listADT:   list.h    ,list.c

·    stackADT:    stack.h   , stack.c

·  queue  ADT:  queue.h  , queue.c

·  priority  queue  ADT:  PQueue. h, PQueue.c

· graph  ADT: Graph.h  ,Graph.c

·  weighted  graph  ADT:  WGraph. h, WGraph.c

You are free to modify any of the six ADTs for the purpose of the assignment (but without

changing the file names). If your program is using one or more of these ADTs, you should submit both

the header and implementation file, even if you have not changed them.

Your  main  program file  tripView.c  should  start with  a  comment:/* …*/  that  contains  the  time complexity of your program in Big-Oh notation, together with a short explanation.

Testing

We have created a script that can automatically test your program. To run this test you can execute the dryrun program that corresponds to this assignment. It expects to find, in the current directory, the

program tripView. c and any of the admissible ADTs (Graph, WGraph, stack, queue, PQueue, list) that your program is using, even if you use them unchanged. You can use dryrun as follows:

prompts 9024 dryrun tripView

Please note: Passing dryrun does not guarantee that your program is correct. You should thoroughly test your program with your own test cases. Submit For this project you will need to submit a file named tripView.c and, optionally, any of the ADTs named Graph, WGraph, stack, queue, PQueue, list that your program is using, even if you have not changed them. You can either submit through WebCMS3 or use a command line. For example, if your program uses the Graph ADT and the queue ADT, then you should submit:

prompts give cs9024 assn tripView.c Graph.h Graph.c queue.h queue.c

Do not forget to add the time complexity to your main source code file tripView.c. You can submit as many times as you like — later submissions will overwrite earlier ones. You can check that your submission has been received on WebCMS3 or by using the following command:

prompt$ 9024 classrun -check assn

Marking

This project will be marked on functionality in the first instance, so it is very important that the output of your program be exactly correct as shown in the examples above. Submissions which score very low on the automarking will be looked at by a human and may receive a few marks, provided the code is well- structured and commented.

Programs that generate compilation errors will receive a very low mark, no matter what other virtues they may have. In general, a program that attempts a substantial part of the&