Cambridge IGCSE Computer Science (9-1) 0984 — 2022 Oct/Nov Paper 2 · Variant 2

This document has 16 pages. Any blank pages are indicated. [Turn over Cambridge IGCSE™(9–1) COMPUTER SCIENCE 0984/22 Paper 2 Problem-solving and Programming October/November 2022 1 hour 45 minutes You must answer on the question paper. No additional materials are needed. INSTRUCTIONS ● Answer all questions. ● Do not attempt Tasks 1, 2 and 3 in the copy of the pre-release material on page 2; these are for information only. ● Use a black or dark blue pen. You may use an HB pencil for any diagrams or graphs. ● Write your name, centre number and candidate number in the boxes at the top of the page. ● Write your answer to each question in the space provided. ● Do not use an erasable pen or correction fluid. ● Do not write on any bar codes. ● Calculators must not be used in this paper. INFORMATION ● The total mark for this paper is 50. ● The number of marks for each question or part question is shown in brackets [ ]. ● No marks will be awarded for using brand names of software packages or hardware. * 4 2 4 4 9 0 0 1 9 9 * DC (CJ/CB) 315858 © UCLES 2022

2 0984/22/O/N/22 © UCLES 2022 Section A You are advised to spend no longer than 40 minutes answering this section. Here is a copy of the pre-release material. DO NOT attempt Tasks 1, 2 and 3 now. Use the pre-release material and your experience from attempting the following tasks before the examination to answer Question 1. Pre-release Material An organisation has a visitor car park with 20 car parking spaces numbered 1 to 20. Car park spaces can be booked by visitors up to two weeks before the date they are needed, as long as a space is available. Visitors request a car parking space by stating the day in the two-week period in which it is required. They give the licence number of the car to be parked and their name. The next available space, beginning at space 1, is allocated and the given data and booking are stored. A system is required to record the car park bookings. Write and test a program or programs for the visitor car park booking system to work for a static period of two weeks: • Your program or programs must include appropriate prompts for the entry of data. Data must be validated on entry. • All outputs, including error messages, need to be set out clearly and understandably. • All variables, constants and other identifiers must have meaningful names. You will need to complete these three tasks. Each task must be fully tested. Task 1 – setting up the booking system Set up suitable data structures to store the car licence numbers and names of visitors who have booked car parking spaces. The data structures should have sufficient capacity to store data for each of the 20 parking spaces for a static period of two weeks. Allow a visitor to request a parking space on any day within the two-week period by entering a number between 1 and 14, inclusive. The system will check that there are spaces available on the day requested, and if so, will ask the visitor to enter their name and car licence number. This data will be stored in the data structures representing the first available parking space for the day requested. The visitor will be told the number of their parking space. At the end of the two-week period, allow all of the data to be deleted ready for the next two-week period. Task 2 – adding accessible parking spaces The visitor car park booking system is to be re-designed to offer accessible parking. Spaces 1 to 5 are named accessible spaces. Spaces 6 to 20 are named general spaces. Extend your program in Task 1 so that: • when a visitor requests a parking space, they are additionally asked if they need an accessible space • if so, they are allocated the first available space beginning at space 1 and finishing at space 20 • if not, they are allocated the first available space beginning at space 20 and finishing at space 6. The system must work so that visitors requiring accessible parking may be allocated any of the 20 spaces, but visitors who do not need accessible parking may only be allocated general spaces. Task 3 – working out car park usage statistics Extend the program to enable the following statistics to be counted and output on request: • The number of accessible spaces used on any of the 14 days. • The number of general spaces used on any of the 14 days. • The total number of spaces used on any of the 14 days. • The number of accessible spaces used in the whole 14-day period. • The number of general spaces used in the whole 14-day period. • The total number of spaces used in the whole 14-day period.

3 0984/22/O/N/22 © UCLES 2022 [Turn over 1 All variables, constants and other identifiers must have meaningful names. (a) (i) Identify one constant you could have used for Task 1 and state its value. Constant … Value … [2] (ii) Identify one array you could have used in Task 1 and describe its use. Array … Use … … … [2] (b) Describe how your program could validate the input for the day number within the two-week period to make sure an appropriate value is entered (part of Task 1). You must include programming statements as part of your answer. … … … … … … … … … … … … [3]

4 0984/22/O/N/22 © UCLES 2022 (c) Write an algorithm to show how your program allocates a parking space if the visitor requires accessible parking (part of Task 2), including all relevant input and output, using pseudocode, programming statements or a flowchart. … … … … … … … … … … … … … … … … … … … … … … … … … … … …

5 0984/22/O/N/22 © UCLES 2022 [Turn over … … … … … … … … … … … … … … … … … … … … … … … … … … … … … [6]

6 0984/22/O/N/22 © UCLES 2022 (d) Explain how your program in Task 2 could be altered so that bookings can be made for any time over a four-week period instead of the current two-week period. Any programming statements used in your answer must be fully explained. … … … … … … … … … … [3] (e) Explain how your program records and outputs the number of accessible and general parking spaces used for the two-week period (part of Task 3). Any programming statements used in your answer must be fully explained. … … … … … … … … … … … … … … … [4]

7 0984/22/O/N/22 © UCLES 2022 [Turn over Section B 2 Draw a line to connect each programming concept to the most appropriate description. [4] 3 Describe the use of verification on input of data when entering a list of items in stock into a database. Explain why verification is necessary. … … … … … … [3] 4 Describe one type of test data that must be used to test if a program accepts valid input data. … … … … [2] counting repetition selection sequence totalling carrying out an action multiple times within a loop structure adding together the numbers in a list of numbers tracking the number of iterations a program has performed in a loop branching off to take a course of action depending on the answer to a question a set of statements to be executed in order Programming concept Description

8 0984/22/O/N/22 © UCLES 2022 5 This pseudocode should allow 500 marks to be entered into the algorithm. If the mark is 80 or greater it is stored in an array for higher marks. If the mark is less than 80, but greater than or equal to 50 it is stored in an array for middle marks. The remaining marks are stored in an array for lower marks. The results from the algorithm are displayed at the end. 01 HighList 0 02 MidList 0 03 LowList 0 04 MarksEntry 0 05 REPEAT 06 INPUT Mark 07 IF Mark >= 80 08 THEN 09 Higher[HighList] MarksEntry 10 HighList HighList + 1 11 ELSE 12 IF Mark >= 50 13 THEN 14 Middle[MidList] Mark 15 MidList MidList 16 ELSE 17 Lower[HighList] Mark 18 LowList LowList + 1 19 ENDIF 20 ENDIF 21 MarksEntry MarksEntry + 1 22 NEXT MarksEntry = 500 23 OUTPUT "You entered ", HighList, " higher marks" 24 OUTPUT "You entered ", MidList, " middle marks" 25 OUTPUT "You entered ", LowList, " lower marks" (a) Identify the four errors in the pseudocode and suggest a correction for each error. Error 1 … Correction … … Error 2 … Correction … … Error 3 … Correction … … Error 4 … Correction … … [4]

9 0984/22/O/N/22 © UCLES 2022 [Turn over (b) The corrected algorithm needs to be changed so that any number of marks may be entered and the algorithm runs until the user tells it to stop. Write the new pseudocode statements that would be needed to achieve this and state where in the algorithm they would be placed. … … … … … … … … … … … … … … [4]

10 0984/22/O/N/22 © UCLES 2022 6 This flowchart represents an algorithm to divide three-digit numbers into hundreds, tens and units. The pre-defined function DIV gives the value of the result of integer division, for example Y = 9 DIV 4 gives the value Y = 2 The pre-defined function MOD gives the value of the remainder of integer division, for example R = 9 MOD 4 gives the value R = 1 START IS Counter > 7? STOP Yes No INPUT Number OUTPUT "Hundreds: ", Hundreds, " Tens: ", Tens, " Units: ", Units Counter 0 IS Number < 100? Yes No IS Number > 999? Yes No Counter Counter + 1 Hundreds Number DIV 100 Temp Number MOD 100 Tens Temp DIV 10 Units Number MOD 10

11 0984/22/O/N/22 © UCLES 2022 [Turn over Complete the trace table for the algorithm using this input data: 97, 876, 4320, 606, 9875, 42, 124 Counter Number Hundreds Temp Tens Units OUTPUT [5]

12 0984/22/O/N/22 © UCLES 2022 7 A school uses a database table, ASSESS, to keep a record of the internal assessments and the number of candidates for each of the subjects in its curriculum. SubjectCode SubjectName Exams Practicals Candidates COMP Computer Science 2 1 200 INFO Information Technology 1 2 200 MATH Mathematics 3 0 350 PHYS Physics 2 1 120 CHEM Chemistry 2 1 120 BIOL Biology 2 1 200 GEOG Geography 2 0 200 HIST History 2 0 250 GEOL Geology 2 0 80 PHED Physical Education 1 2 350 FREN French 2 2 120 ENGL English 2 2 350 This database only allows the data types: • text • number • currency • Boolean. (a) (i) State the most appropriate data type for the fields SubjectCode and Exams. SubjectCode … Exams … [1] (ii) State one reason why the Candidates field could not be of the Boolean data type. … … [1]

13 0984/22/O/N/22 © UCLES 2022 (b) Show the output given by the query-by-example grid. Field: SubjectName Practicals Candidates Table: ASSESS ASSESS ASSESS Sort: Ascending Show: 3 3 Criteria: <1 or: … … … … … … [3] (c) Complete the query-by-example grid to output the subjects with fewer than 150 candidates. Display only the SubjectCode, SubjectName and Candidates fields in order of the number of candidates from largest to smallest. Field: Table: Sort: Show: Criteria: or: [3]

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16 0984/22/O/N/22 © UCLES 2022 Permission to reproduce items where third-party owned material protected by copyright is included has been sought and cleared where possible. Every reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the publisher will be pleased to make amends at the earliest possible opportunity. To avoid the issue of disclosure of answer-related information to candidates, all copyright acknowledgements are reproduced online in the Cambridge Assessment International Education Copyright Acknowledgements Booklet. This is produced for each series of examinations and is freely available to download at www.cambridgeinternational.org after the live examination series. Cambridge Assessment International Education is part of Cambridge Assessment. Cambridge Assessment is the brand name of the University of Cambridge Local Examinations Syndicate (UCLES), which is a department of the University of Cambridge. BLANK PAGE

This document consists of 15 printed pages. © UCLES 2022 [Turn over Cambridge IGCSE™ (9–1) COMPUTER SCIENCE 0984/22 Paper 2 Problem-solving and Programming October/November 2022 MARK SCHEME Maximum Mark: 50 Published This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of the examination. It shows the basis on which Examiners were instructed to award marks. It does not indicate the details of the discussions that took place at an Examiners’ meeting before marking began, which would have considered the acceptability of alternative answers. Mark schemes should be read in conjunction with the question paper and the Principal Examiner Report for Teachers. Cambridge International will not enter into discussions about these mark schemes. Cambridge International is publishing the mark schemes for the October/November 2022 series for most Cambridge IGCSE™, Cambridge International A and AS Level components and some Cambridge O Level components.

0984/22 Cambridge IGCSE (9–1) – Mark Scheme PUBLISHED October/November 2022 © UCLES 2022 Page 2 of 15 Generic Marking Principles These general marking principles must be applied by all examiners when marking candidate answers. They should be applied alongside the specific content of the mark scheme or generic level descriptors for a question. Each question paper and mark scheme will also comply with these marking principles. GENERIC MARKING PRINCIPLE 1: Marks must be awarded in line with: • the specific content of the mark scheme or the generic level descriptors for the question • the specific skills defined in the mark scheme or in the generic level descriptors for the question • the standard of response required by a candidate as exemplified by the standardisation scripts. GENERIC MARKING PRINCIPLE 2: Marks awarded are always whole marks (not half marks, or other fractions). GENERIC MARKING PRINCIPLE 3: Marks must be awarded positively: • marks are awarded for correct/valid answers, as defined in the mark scheme. However, credit is given for valid answers which go beyond the scope of the syllabus and mark scheme, referring to your Team Leader as appropriate • marks are awarded when candidates clearly demonstrate what they know and can do • marks are not deducted for errors • marks are not deducted for omissions • answers should only be judged on the quality of spelling, punctuation and grammar when these features are specifically assessed by the question as indicated by the mark scheme. The meaning, however, should be unambiguous. GENERIC MARKING PRINCIPLE 4: Rules must be applied consistently, e.g. in situations where candidates have not followed instructions or in the application of generic level descriptors.

0984/22 Cambridge IGCSE (9–1) – Mark Scheme PUBLISHED October/November 2022 © UCLES 2022 Page 3 of 15 GENERIC MARKING PRINCIPLE 5: Marks should be awarded using the full range of marks defined in the mark scheme for the question (however; the use of the full mark range may be limited according to the quality of the candidate responses seen). GENERIC MARKING PRINCIPLE 6: Marks awarded are based solely on the requirements as defined in the mark scheme. Marks should not be awarded with grade thresholds or grade descriptors in mind. Please note the following further points: The words in bold in the mark scheme are important text that needs to be present, or some notion of it needs to be present. It does not have to be the exact word, but something close to the meaning. If a word is underlined, this exact word must be present. A single forward slash means this is an alternative word. A double forward slash means that this is an alternative mark point. Ellipsis (…) on the end of one-mark point and the start of the next means that the candidate cannot get the second mark point without being awarded the first one. If a mark point has an ellipsis at the beginning, but there is no ellipsis on the mark point before it, then this is just a follow-on sentence and can be awarded without the previous mark point.

0984/22 Cambridge IGCSE (9–1) – Mark Scheme PUBLISHED October/November 2022 © UCLES 2022 Page 4 of 15 Question Answer Marks Section A 1(a)(i) Many correct answers, the name used must be meaningful. The name given is an example only. One mark per mark point, max two • Constant NumberDays … • Value … 14 Task 1 – setting up the booking system Set up suitable data structures to store the car licence numbers and names of visitors who have booked car parking spaces. The data structures should have sufficient capacity to store data for each of the 20 parking spaces for a static period of two weeks. Allow a visitor to request a parking space on any day within the two-week period by entering a number between 1 and 14, inclusive. The system will check that there are spaces available on the day requested, and if so, will ask the visitor to enter their name and car licence number. This data will be stored in the data structures representing the first available parking space for the day requested. The visitor will be told the number of their parking space. At the end of the two-week period, allow all of the data to be deleted ready for the next two-week period. 2 1(a)(ii) Many correct answers, the name used must be meaningful. The name given is an example only. One mark per mark point, max two • Array LicenceNumbers … • Use … storing the licence numbers of the cars to be parked 2

0984/22 Cambridge IGCSE (9–1) – Mark Scheme PUBLISHED October/November 2022 © UCLES 2022 Page 5 of 15 Question Answer Marks 1(b) One mark per mark point, max two MP1 use a (range) check to check for values between 1 and 14 MP2 use a (type) check to ensure an integer is entered MP3 … using an (appropriate) IF/conditional statement MP4 outputs an error message if a new input is required MP5 re-enter data using WHILE/REPEAT loop until a valid entry has been made One mark MP6 appropriate line of code / construct to answer the question Example code INPUT Day WHILE Day < 1 OR Day > 14 DO OUTPUT "You must enter a number between 1 and 14 inclusive" INPUT Day ENDWHILE 3

0984/22 Cambridge IGCSE (9–1) – Mark Scheme PUBLISHED October/November 2022 © UCLES 2022 Page 6 of 15 Question Answer Marks 1(c) One mark per mark point, max six MP1 input for day number or to choose accessible parking … MP2 … both inputs with appropriate prompts MP3 conditional statement to check if accessible parking is required MP4 initialisation of variable for the first accessible space MP5 checking if current array element is an available space MP6 correct loop to check all array elements for the day MP7 … until an available space is found (or not) MP8 input car licence number and name (with or without prompts) MP9 … and store them in the correct array position(s) MP10 appropriate output for space available or no space available MP11 appropriate output for allocated parking space details Task 2 – adding accessible parking spaces The visitor car park booking system is to be re-designed to offer accessible parking. Spaces 1 to 5 are named accessible spaces. Spaces 6 to 20 are named general spaces. Extend your program in Task 1 so that: • when a visitor requests a parking space, they are additionally asked if they need an accessible space – if so, they are allocated the first available space beginning at space 1 and finishing at space 20 – if not, they are allocated the first available space beginning at space 20 and finishing at space 6. The system must work so that visitors requiring accessible parking may be allocated any of the 20 spaces, but visitors who do not need accessible parking may only be allocated general spaces. 6

0984/22 Cambridge IGCSE (9–1) – Mark Scheme PUBLISHED October/November 2022 © UCLES 2022 Page 7 of 15 Question Answer Marks 1(c) Example answer //Assume LicenceNumber array has been initialised with the null string OUTPUT "Enter the number of the day in which you require parking " INPUT Day OUTPUT "Do you require an accessible space? (Y or N)" INPUT Accessible IF Accessible = "Y" THEN SpaceAllocated  FALSE Space  (Day - 1) * 20 REPEAT IF LicenceNumbers[Space] = "" THEN OUTPUT "Enter your car licence number " INPUT LicenceNumbers[Space] SpaceAllocated  TRUE ENDIF Space  Space + 1 UNTIL SpaceAllocated OR Space = (Day - 1) * 20 + 20 IF NOT SpaceAllocated THEN OUTPUT "No space available" ELSE OUTPUT "You are allocated space: ", Space – (Day – 1) * 20 ENDIF ENDIF

0984/22 Cambridge IGCSE (9–1) – Mark Scheme PUBLISHED October/November 2022 © UCLES 2022 Page 8 of 15 Question Answer Marks 1(d) Explanation of how the following could be done: One mark per mark point, max three MP1 change the max constant to 560 / 28 MP2 change the output message for the user to say that the range of days entered must be from 1 to 28 MP3 alter the validation to allow an input of 1 to 28 MP4 change the size of the array that stores licence numbers / names so that it can hold the additional data MP5 ensure that all loops that access the stored data for retrieval or erasing of data include the new full range 3 1(e) Explanation of how the following could be done: One mark per mark point, max four MP1 initialise counting variable(s) … MP2 … for accessible spaces and general spaces before any spaces have been allocated MP3 increment the counter(s) … MP4 … for accessible spaces and general spaces MP5 maintain both counters for the full two-week cycle MP6 output to show the total number of accessible and general spaces allocated so far, with suitable messages • Task 3 – working out car park usage statistics • Extend the program to enable the following statistics to be counted and output on request: • The number of accessible spaces used on any of the 14 days. • The number of general spaces used on any of the 14 days. • The total number of spaces used on any of the 14 days. • The number of accessible spaces used in the whole 14-day period. • The number of general spaces used in the whole 14-day period. • The total number of spaces used in the whole 14-day period. 4

0984/22 Cambridge IGCSE (9–1) – Mark Scheme PUBLISHED October/November 2022 © UCLES 2022 Page 9 of 15 Question Answer Marks Section B 2 One mark for each correct line, max four Programming concept Description 4 counting repetition selection sequence totalling carrying out an action multiple times within a loop structure adding together the numbers in a list of numbers tracking the number of iterations a program has performed in a loop branching off to take a course of action depending on the answer to a question a set of statements to be executed in order

0984/22 Cambridge IGCSE (9–1) – Mark Scheme PUBLISHED October/November 2022 © UCLES 2022 Page 10 of 15 Question Answer Marks 3 One mark per mark point, max three MP1 verification is used to make sure the items in stock do not change from the original when they are input // verification is used to make sure the items in stock do not change from what was intended to be input // verification is used to make sure the items are accurately copied MP2 enter each item in stock twice / double entry // visual check MP3 matching description of the type of check stated in MP2 Example answers Double entry [1] enter data twice and only accept identical values [1] Visual check [1] look at the data that has been entered and confirm it matches [1] 3 Question Answer Marks 4 One mark per mark point, max two • type of test data … • … description of test data Example answers Normal data (1) data that would be accepted by the program (1) Boundary / extreme data (1) data that is on the acceptable limits (1) 2

0984/22 Cambridge IGCSE (9–1) – Mark Scheme PUBLISHED October/November 2022 © UCLES 2022 Page 11 of 15 Question Answer Marks 5(a) One mark per mark point, max four • Line 09 / Higher[HighList]  MarksEntry should be Higher[HighList]  Mark • Line 15 / MidList  MidList should be MidList  MidList + 1 • Line 17 / Lower[HighList]  Mark should be Lower[LowList]  Mark • Line 22 / NEXT MarksEntry = 500 should be UNTIL MarksEntry = 500 Corrected algorithm 01 HighList  0 02 MidList  0 03 LowList  0 04 MarksEntry  0 05 REPEAT 06 INPUT Mark 07 IF Mark >= 80 08 THEN 09 Higher[HighList]  Mark 10 HighList  HighList + 1 11 ELSE 12 IF Mark >= 50 13 THEN 14 Middle[MidList]  Mark 15 MidList  MidList + 1 4

0984/22 Cambridge IGCSE (9–1) – Mark Scheme PUBLISHED October/November 2022 © UCLES 2022 Page 12 of 15 Question Answer Marks 5(a) 16 ELSE 17 Lower[LowList]  Mark 18 LowList  LowList + 1 19 ENDIF 20 ENDIF 21 MarksEntry  MarksEntry + 1 22 UNTIL MarksEntry = 500 23 OUTPUT "You entered ", HighList, " higher marks" 24 OUTPUT "You entered ", MidList, " middle marks" 25 OUTPUT "You entered ", LowList, " lower marks"

0984/22 Cambridge IGCSE (9–1) – Mark Scheme PUBLISHED October/November 2022 © UCLES 2022 Page 13 of 15 Question Answer Marks 5(b) One mark per mark point, max four MP1 Set up a condition to end the input MP2 The correct placement of the condition MP3 Set up the test MP4 The correct placement of the test MP5 Removal of MarksEntry counter from the original algorithm Example answers Testing at the end of the algorithm OUTPUT "Do you want to enter another mark?" INPUT AnotherMark UNTIL AnotherMark = "No" should replace line 22 at end of loop The MarksEntry counter can be removed // Lines 4 and 21 are not required / can be removed Testing at the beginning of the algorithm AnotherMark = "Yes" WHILE AnotherMark = "Yes" DO should replace line 05 at the start of the loop OUTPUT "Do you want to enter another mark?" INPUT AnotherMark ENDWHILE should replace line 22 at end of loop The MarksEntry counter can be removed // Lines 4 and 21 are not required / can be removed Terminal condition OUTPUT "Enter -1 to end the program" should be placed before the loop and / or before the input in 06 IF MARK <> -1 THEN should be placed between lines 06 and 07 The MarksEntry counter can be removed // Lines 4 and 21 are not required / can be removed UNTIL Mark = -1 should be placed at line 22 4

0984/22 Cambridge IGCSE (9–1) – Mark Scheme PUBLISHED October/November 2022 © UCLES 2022 Page 14 of 15 Question Answer Marks 6 One mark per mark point, max five MP1 correct Counter and Number columns MP2 correct Hundreds column MP3 correct Temp and Tens columns MP4 correct Units column MP5 correct OUTPUT column Counter Number Hundreds Temp Tens Units OUTPUT 0 1 97 2 876 8 76 7 6 Hundreds: 8 Tens: 7 Units: 6 3 4320 4 606 6 6 0 6 Hundreds: 6 Tens: 0 Units: 6 5 9875 6 42 7 124 1 24 2 4 Hundreds: 1 Tens: 2 Units: 4 8 5

0984/22 Cambridge IGCSE (9–1) – Mark Scheme PUBLISHED October/November 2022 © UCLES 2022 Page 15 of 15 Question Answer Marks 7(a)(i) SubjectCode Text Exams Number Data types must match those given in the question. 1 7(a)(ii) The Boolean data type can only have one of two values // the Candidates field has more than two possible values. 1 7(b) One mark per mark point, max three • correct data • correct layout • correct order Expected answer Geography 200 Geology 80 History 250 Mathematics 350 3 7(c) One mark per mark point, max three • correct fieldnames and table names • correct sort and show rows • correct search criteria Field: SubjectCode SubjectName Candidates Table: ASSESS ASSESS ASSESS Sort: Descending Show:      Criteria: <150 or: 3