1 All variables, constants and other identifiers must have meaningful names. (a) Identify the variable that you used to store the student’s answer in Task 1. Give the most appropriate data type for this variable. Explain how your program ensured that any data entered for the answer was valid. Variable … Data type … Validation … … … … [4] (b) Identify and give the data type of a different variable, that you could have used in Task 2. State the use of this variable in Task 2. Variable … Data type … Use … … [3] (c) Write an algorithm for Task 1, using either pseudocode, programming statements or a flowchart. … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … [6] (d) Explain how your program completed Task 3. Include any programming statements that you have added to Task 1 and fully explain the purpose of each statement. … … … … … … … … … … … … … … … … … … … … … … … [4] (e) Explain how you could alter Task 1 to change the quiz to: • display three alternative answers for each question • allow the student to choose one of these answers … … … … … … … … … … … … … … … … … … … … … … … [3] Section B

1(a) Variable answer (example only) Data type integer/int Validation two distinct different points OR one point and an expansion One mark per mark point, max two – restricted input to positive numbers – checked if input was numeric – ensured that input was a whole number / integer – checked if a value was input Or one point and an expansion two marks, for example – restricted input to positive numbers (1) by using a range/limit check / REPEAT… UNTIL looping until value greater than zero (1) – checked if input was numeric (1) by using a type check (1) – ensured the value input was a whole number (1) any suitable method e.g. rounding to whole number – checked if a value was input (1) by using a presence check (1) 4 1(b) Variable noAttempts (example only) Data type integer/int Use storing the number of attempts a pupil has made on a question 3 1(c) One mark per mark point, max six MP1 initialisation (must include number of correct answers) MP2 input name and table number with prompts MP3 validate table number and reinput MP4 ensure each question uses a different multiplier MP5 display question MP6 input and validate answer MP7 check if answer correct MP8 update score appropriately MP9 repeat for 5 questions MP10 display score and name at end … MP11 …with an attempt to display an appropriate message dependent on score Example Score = 0 Multiplier[1] ← 2 Multiplier[2] ← 5 Multiplier[3] ← 7 Multiplier[4] ← 8 Multiplier[5] ← 11 OUTPUT "Multiplication Table Test" OUTPUT "Please enter your name" INPUT Name REPEAT OUTPUT "Please enter the table (2 to 12) you would like to be tested" INPUT Table UNTIL (Table >=2) AND (Table 0 AND Answer = INT(Answer) IF Answer = Multiplier[Count] * Table THEN Score ← Score + 1 ENDIF NEXT OUTPUT (Name, " your score is ", Score) IF Score = 5 THEN OUTPUT ("Well done full marks") ELSE OUTPUT ("Have another practice") ENDIF 6 1(d) Explanation One mark per mark point illustrated with a suitable programming statement, max four MP1 extra prompt and input to choose the number of questions and/or mixed set MP2 method of choosing number of questions and/or mixed set MP3 extra prompt and input for number of questions MP4 explanation of validation for either input MP5 how the end value for the question loop was changed if required MP6 how the program was changed to allow for mixed tables MP7 … how the program ensured that the test used more than one multiplication table 4 1(e) Explanation One mark per mark point, max three MP1 how to provide 3 answers, including the correct one MP2 how to ensure that all 3 answers are different MP3 how 3 answers are displayed e.g. output all 3 answers as a numbered list MP4 how to select the correct answer e.g. input the number of the correct MP5 how to ensure that the correct answer is not always in the same position 3 Section B (a) To earn marks, you must identify a suitable variable name (like 'answer'), state its data type as integer, and provide two distinct points about how input validation was performed (e.g., restricting to positive numbers and checking if numeric), or one point with a clear expansion. (b) You need to identify a different variable (like 'noAttempts'), state its integer data type, and explain its purpose in Task 2, such as storing the number of attempts.

1 All variables, constants and other identifiers must have meaningful names. (a) Identify and give the data type and use of one array that you could have used for Task 1. Array … Data type … Use … [3] (b) Describe two validation checks that could be used when inputting the number of tickets to buy for Task 2. For each validation check give one example of normal data and one example of erroneous data. Validation check 1 … … … Normal data … Erroneous data … Validation check 2 … … … Normal data … Erroneous data … [6] (c) Write an algorithm for the part of Task 2 that inputs the tickets required, calculates the total price for the ticket(s) purchased by a passenger including a group discount (if applicable) and updates the data structures used for the totals. Use either pseudocode, programming statements or a flowchart. … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … [6] (d) Explain how your program completed Task 3. Include any programming statements that you have used and fully explain the purpose of each statement. … … … … … … … … … … … … … … … … … … … … … … … [5] Section B starts on page 8 Section B

Section A 1(a) Array TrainUpPassengers // TrainUpPassengers[] Data type Integer/int Use storing the number of passengers on the train journeys up Many correct answers, this is an example. 3 1(b) One mark for description, one mark for normal data and one mark for erroneous data for two checks Validation check (type check) to check that the number entered is a whole number / integer Normal data 34 Erroneous data two // 1.5 Validation check (range check) to check that the value of the number entered is between 1 and 80 / 480 inclusive Normal data 34 Erroneous data 99 // 500 Validation check (presence check) to check that a value has been entered Normal data 34 // any data entered Erroneous data “” // blank // no data entered Validation check (length check) to check that a value has 3 digits or fewer // between 1 and 3 digits Normal data 345 Erroneous data 3456 Many correct answers, the data are examples only. 6 1(c) Any six from: MP1 Input number of tickets MP2 Input train up mountain and train down mountain MP3 Suitable prompts seen for inputs that are included MP4 Check that tickets are available on selected train(s) MP5 If available calculate price of tickets … MP6 … calculation includes discount if required MP7 Update total passengers / seats available for a train MP8 Update total passengers / seats available for up train and down train MP9 Update total cost for a train MP10 Update total cost for up train and down train Example answers OUTPUT "How many tickets" INPUT NoTickets OUTPUT "Which Train up the mountain? 1, 2, 3 or 4" INPUT UpNumber OUTPUT "Which Train down the mountain? 1, 2, 3 or 4" INPUT DownNumber IF (DownNumber = 4 AND TrainUp[UpNumber] + NoTickets <= 480 AND TrainDown[DownNumber] + NoTickets <= 640) OR (TrainUp[UpNumber] + NoTickets <= 480 AND TrainDown[DownNumber] + NoTickets <= 480) THEN Cost ← (NoTickets – NoTickets DIV 10) * 50 TrainUp[UpNumber] ← TrainUp[UpNumber] + NoTickets TrainDown[DownNumber] ← TrainUp[DownNumber] + NoTickets TrainUpTotal[UpNumber] ← TrainUpTotal[UpNumber] + Cost / 2 TrainDownTotal[DownNumber] ← TrainDownTotal[DownNumber] + Cost / 2 ENDIF 6 1(c) Yes Yes START OUTPUT "Tickets" INPUT Tickets Cost ← (NoTickets – NoTickets DIV 10) * 50 TrainUp[UpNo] ← TrainUp[UpNo] + NoTickets TrainDown[DownNo] ← TrainUp[DownNo] + NoTickets TrainUpTotal[UpNo] ← TrainUpTotal[UpNo] + Cost / 2 TrainDownTotal[DownNo] ← TrainDownTotal[DownNo] + Cost / 2 END Is Tickets <= UpTickets[UpNo] AND Tickets <= DownTickets[DownNo]? No OUTPUT "Up Train" INPUT UpNo OUTPUT "Down Train" INPUT DownNo 1(d) Explanation Any five from: MP1 How the program displayed the number of passengers for a journey ... MP2 … how completed for all trains MP3 How the program displayed the amount of money taken for a journey … MP4 … how completed for all trains MP5 How the program calculated the total number of passengers MP6 How the program calculated the total money taken MP7 How the program attempted to select the train journey with the most passengers MP8 How the program attempted to dealt with more than one train being the most popular MP9 How the program displayed the results with suitable messages Programming statements must be given with each explanation. 5 Section B 2(a) Any six from: MP1 Initialisation of large and small variables e.g. Large ← 0 Small ← 1000 MP2 Use of a loop for 500 entries // or 499 if initialisation done on first correct entry MP3 Input with prompt MP4 Attempt at checking the range of 1 to 999 for input MP5 … working range check MP6 Checking for a whole number MP7 Selecting largest number MP8 Selecting smallest number MP9 Calculating the range MP10 Outputting the largest, smallest and range with message Large ← 0 Small ← 1000 FOR Count ← 1 TO 500 REPEAT OUTPUT "Enter a whole number between 1 and 999" INPUT Number UNTIL Number >= 1 AND Number Large THEN Large ← Number ENDIF NEXT Range ← Large – Small OUTPUT "Largest number is ", Large, " Smallest number is ", Small, " Range of numbers is ", Range 6 (a) To earn marks, you must identify a suitable array name (e.g., TrainUpPassengers), state its data type (Integer/int), and clearly explain its purpose (e.g., storing the number of passengers for train journeys). (b) For each of two validation checks, you need to describe the check (e.g., type check, range check), provide an example of normal data that would pass, and an example of erroneous data that would fail.

1 All variables, constants and other identifiers must have meaningful names. (a) Identify one constant that you could have used for Task 1. Give the value that would be assigned to this constant. State the use of this constant. Constant … Value … Use … … [3] (b) Describe the arrays that you have set up in Task 1 to record today’s data about the squash courts. … … … … … … … … [4] (c) Explain how your program generates a unique 4-digit code for each booking. … … … … … … [3] (d) Write an algorithm for Task 2. You do not need to display updated court availability. Use either pseudocode, programming statements or a flowchart. Assume that Task 1 has been completed. … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … [6] (e) Explain how your program completed the part of Task 3 which calculates the total number of squash court bookings, finds the court(s) with the most bookings and displays this information. Include any programming statements that you have used and fully explain the purpose of each statement. … … … … … … … … … … … … … … … … … … … … … … … [4] Section B starts on Page 8 Section B

Section A 1(a) Constant NoCourts // NoSessions // NoBookingSlots Value 8 // 10 // 80 Use Storing the number of courts / sessions available / times and courts available for booking 3 1(b) Any four from: Any three from MP1 Identifier / name of array used MP2 Description of purpose of an identified array MP3 Length of an identified array used MP4 Type of data in an identified array MP5 Explanation of number of arrays used, must be capable of storing all data required MP6 Sample data for an identified array One mark MP7 Identifying more than one array E.g.4 arrays of ten elements for each squash court, for example for squash court 1 Availability1 of type Boolean, Guest1, Mobile1 and Code1 all type string 4 1(c) Any three from: MP1 Setting the first code number MP2 How to find subsequent code numbers MP3 How to ensure they were unique MP4 How to ensure they were exactly 4 digits 3 1(d) Any six from: MP1 Input time MP2 … with prompt MP3 Check each court MP4 If court not booked … MP5 … set as booked MP6 Input name, mobile number MP7 Calculate unique 4-digit code MP8 Store name, mobile number and 4-digit code in an array MP9 Display mobile number and 4-digit code with suitable message MP10 Change mobile number if necessary Sample OUTPUT ("Which time do you want to book a squash court") INPUT BookTime Booked ← FALSE CourtNumber ← 0 IF BookTime >= 8 AND BookTime <= 17 THEN BookTime ← BookTime - 7 IF Available1[BookTime] THEN Available1[BookTime] ← FALSE; CourtNumber ← 1; Booked ← TRUE ENDIF IF NOT Booked AND Available2[BookTime] THEN Available2[BookTime] ← FALSE; CourtNumber ← 2; Booked ← TRUE ENDIF IF NOT Booked AND Available3[BookTime] THEN Available3[BookTime] ← FALSE; CourtNumber ← 3; Booked ← TRUE ENDIF IF NOT Booked AND Available4[BookTime] THEN Available4[BookTime] ← FALSE; CourtNumber ← 4; Booked ← TRUE ENDIF IF NOT Booked AND Available5[BookTime] THEN Available5[BookTime] ← FALSE; CourtNumber ← 5; Booked ← TRUE ENDIF IF NOT Booked AND Available6[BookTime] THEN Available6[BookTime] ← FALSE; CourtNumber ← 6; Booked ← TRUE ENDIF IF NOT Booked AND Available7[BookTime] THEN Available7[BookTime] ← FALSE; CourtNumber ← 7; Booked ← TRUE ENDIF 6 1(d) IF NOT Booked AND Available8[BookTime] THEN Available8[BookTime] ← FALSE; CourtNumber ← 8; Booked ← TRUE ENDIF IF NOT Booked OUTPUT("No court available at ", BookTime + 7) ENDIF IF Booked THEN OUTPUT ("Please enter your name") INPUT Name Code ← Code + 1 Correct ← "N" WHILE Correct = "N" DO OUTPUT ("Please enter your mobile number") INPUT Mobile OUTPUT ("Is Your mobile number correct Y/N? ", Mobile, " Your court number is ", CourtNumber, " Your entry code is ", Code) INPUT Correct ENDWHILE CASE CourtNumber OF 1 : Guest1[BookTime}← Name; Mobile1[BookTime] ← Mobile; Code1[BookTime] ← Code 2 : Guest2[BookTime}← Name; Mobile2[BookTime] ← Mobile; Code2[BookTime] ← Code 3 : Guest3[BookTime}← Name; Mobile3[BookTime] ← Mobile; Code3[BookTime] ← Code 4 : Guest4[BookTime}← Name; Mobile4[BookTime] ← Mobile; Code4[BookTime] ← Code 5 : Guest5[BookTime}← Name; Mobile5[BookTime] ← Mobile; Code5[BookTime] ← Code 6 : Guest6[BookTime}← Name; Mobile6[BookTime] ← Mobile; Code6[BookTime] ← Code 7 : Guest6[BookTime}← Name; Mobile7[BookTime] ← Mobile; Code7[BookTime] ← Code 8 : Guest8[BookTime}← Name; Mobile8[BookTime] ← Mobile; Code8[BookTime] ← Code ENDCASE NoCoutsBooked[BookTime] ← NoCoutsBooked[BookTime] - 1 ELSE OUTPUT ("Court not booked”) ENDIF 1(e) Explanation Any four from MP1 How the program totalled the number of bookings MP2 How the program displayed the total number of bookings MP3 How the program calculated the number of times each court was booked MP4 How the program selected the highest value for times a court was booked MP5 How the program displayed the court that was most booked Programming statements must be included and must be explained. 4 Section B 2(a) Line 1 should be Counter ← 0 Line 3 RandNum[Counter] ← Rand(1, 100)should be RandNum[Counter] ← Rand(1, 101) Line 4 Counter ← Counter + 2 should be Counter ← Counter + 1 Line 5 UNTIL Count = 50 // UNTIL Counter = 50 1 Counter ← 0 2 REPEAT 3 RandNum[Counter} ← Rand(1, 100) 4 Counter ← Counter + 1 5 UNTIL Counter >= 50 Or Line 3 RandNum[Counter] should be RandNum[Count] Line 3 Rand(1, 100)should be Rand(1, 101) Line 4 Counter ← Counter + 2 should be Count ← Count + 1 Line 5 UNTIL Count = 50 // UNTIL Count = 50 1 Count ← 0 2 REPEAT 3 RandNum[Count} ← Rand(1, 100) 4 Count ← Count + 1 5 UNTIL Count >= 50 4 2(b) One mark for each correct line FOR Count ← 0 TO 49 // FOR Count ← 1 TO 50 RandNum[Count] ← Rand(1, 101) / Rand(0, 101) NEXT // NEXT Count 3 2(c) Precondition loop // WHILE … DO … ENDWHILE 1 (a) To earn marks, you must identify a constant from the task (like 'NoCourts'), provide its correct numerical value (e.g., '8'), and clearly state its purpose (e.g., 'Storing the number of courts'). (b) To score marks, you need to describe the arrays by providing their identifier/name, purpose, length, data type, and explain why multiple arrays are used if applicable, or give sample data. Identifying more than one array also earns a mark. (c) Marks are awarded for explaining how the first code is set, how subsequent codes are found, how uniqueness is ensured, and how the 4-digit length is maintained. (d) To earn marks, you need to describe the steps of the booking process: inputting time with a prompt, checking court availability, setting a court as booked, inputting customer details, calculating a unique 4-digit code, storing all relevant data in an array, and displaying the mobile number and code with a suitable message.

1 All variables, constants and other identifiers must have meaningful names. (a) (i) Identify one variable you could have used for Task 2 and state its use. Variable … Use … … … [2] (ii) Describe the arrays you could have used in Task 1. Include the name, data type, use and sample data for each array. … … … … … … … … … … … … [5] (b) Describe how you could validate the data entry for the input of the codes for the different stages of the journey in Task 2. … … … … … … [3] (c) Write an algorithm to show how your program carries out Task 3, using either pseudocode, programming statements or a flowchart. Assume Tasks 1 and 2 have already been completed. … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … [6] (d) Explain how your program could be changed to count and store the number of bookings made by each passenger. Then, after ten bookings have been made by a passenger, apply an additional 10% discount to every future booking. Any programming statements used in your answer must be fully explained. … … … … … … … … … … … … … … … … … … … … … … … … … … … [4] Section B

Section A 1(a)(i) One mark per point • Variable PassengerID// StartStage • Use Storing the unique ID number of the passenger// Storing/inputting the start stage of the journey 2 1(a)(ii) One mark per point MP1 Name of array MP2 Data type of array MP3 Sample data for array MP4 Use of array MP5 At least two complete arrays with all of the above Array name Data type Sample data Use JourneyStage1 string C1 to store the code for the home to start station PriceStage1 real 1.50 to store the price of first stage of the journey 5 1(b) One mark per bullet point MP1 Use of validation check, e.g. range check, type check, presence check, length check, format check MP2 Use of conditional statement to check if the validation fails ... MP3 … a re-entry is requested MP4 Use of loop to repeat the process until an acceptable answer is input MP5 More than one appropriate validation check used / described. 3 1(c) Any six from: MP1 Conditional statement to check departure time against 10:00 MP2 … calculate 40% discount // calculate 60% of the original price MP3 … calculate discounted total price MP4 Output the discounted total price MP5 Output the booking details with suitable messages MP6 Input with prompt for passenger confirmation … MP7 … attempt at action following the confirmation input MP8 Repeating booking data entry if incorrect MP9 Re-checking journey details for correctness 6 1(c) Example answer // Tasks 1 and 2 completed IF CollectedTime[Index] > 10:00 THEN JourneyCost[Index] ← JouneyCost[Index] * 0.6 ENDIF PRINT "Your journey cost is: ", JourneyCost[Index] PRINT "Your journey details are: ", PassengerID[Index], JourneyTime[Index], JourneyCodes[Index], JourneyID[Index] PRINT "Are these details correct? (Y or N)" INPUT Correct IF Correct = "N" THEN WHILE Correct = "N" PRINT "Re-enter your journey details" PRINT "Correct passenger ID " INPUT PassengerID[Index] PRINT "Correct journey time " INPUT JourneyTime[Index] PRINT "Correct journey codes " INPUT JourneyCodes[Index] PRINT "Your revised journey details are: ", PassengerID[Index], JourneyTime[Index], JourneyCodes[Index] PRINT "Are these details correct? (Y or N)" INPUT Correct ENDWHILE ENDIF //Program continues 1(d) Explanation of how each of the following could be done Any four from: MP1 Declaring/using a counter to store the number of bookings for each passenger MP2 Updating the counter for the number of bookings made by each passenger MP3 Attempt to check the number of bookings … MP4 … for the correct condition e.g. if the number of bookings is more than 10 / equal to 10 MP5 Apply the extra discount to the total price of future journeys 4 Section B 2 One mark for two correct rows Two marks for three correct rows Three marks for four correct rows. Statement Validation () Verification () Neither () a check where data is re-entered to make sure no errors have been introduced during data entry  an automatic check to make sure the data entered has the correct number of characters  a check to make sure the data entered is sensible  a check to make sure the data entered is correct  3

1 All variables, constants and other identifiers must have meaningful names. (a) Identify one constant that you could have used for Task 1. Give the value that would be assigned to this constant. State the use of this constant. Constant … Value … Use … … [3] (b) Describe the arrays that you have set up in Task 1 to record today’s data about the restaurant tables. … … … … … … … … [4] (c) Sometimes the restaurant has fewer tables available for a session. Explain how you would change your Task 1 program to allow input of the number of tables available for a session. … … … … … … [3] (d) Part of Task 2 is to check if a table is available. Write an algorithm to do this, using either pseudocode, programming statements or a flowchart. Assume that Task 1 has been completed. … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … [6] (e) Explain how your program for Task 3 updated Task 2. Include any programming statements used and fully explain the purpose of each statement. … … … … … … … … … … … … … … … … … … … … … … … [4] Section B starts on Page 8. Section B

Section A 1(a) Constant name MaxNoTables Value 20 Use Storing the maximum number of tables available for a session 3 1(b) Any three from: MP1 Identifier / name of array used MP2 Description of purpose of an identified array MP3 Length of an identified array used MP4 Type of data in an identified array MP5 Explanation of number of arrays used, must be capable of storing all data required MP6 Sample data for an identified array One mark MP7 Identifying more than one array E.g. 3 sets of 4 arrays of twenty elements for each session, for example for lunch, TableLunch of type Boolean, PassengerLunch, CabinLunch and DietReqLunch all type string 4 1(c) Any three from: MP1 Input the maximum number of tables available for a session MP2 Input the maximum number of tables available for every session MP3 Storing each value input in a variable / an array MP4 Validation check MP5 Change the constant used for number of tables to a variable MP6 Using the value input instead of 20 for max value for loop counter etc 3 1(d) Any six from: MP1 Input session MP2 … with prompt MP3 Validate input MP4 Check number of tables available / check each table … MP5 … for the session that has been input MP6 If no tables available any session that has been input MP7 … output suitable message Sample REPEAT OUTPUT "Which session do you want to book a table?" INPUT Session UNTIL Session >= 1 AND Session <= 3 IF TablesAvailable[Session] = 0 THEN OUTPUT "No tables available " ENDIF 6 1(e) Explanation Any four from: MP1 Any changes required for the Array data types in Task 1 MP2 How the program displayed the options in Task 3 MP3 How the program selected the choice in Task 3 MP4 How the program dealt with incorrect choices in Task 3 MP5 How the program counted number of tables with vegetarian diners MP6 How the program counted number of tables with vegan diners MP7 How the program output number of tables with vegetarian/vegan diners Programming statements should be used and must be explained. 4 Section B 2(a) Line 1 should be Counter Line 2 should be < 50 Line 3 should be RandUp(0,100) // RandUp(-1,100) Line 4 should be Counter ← Counter + 1 1 Counter ← 0 2 WHILE Counter < 50 DO 3 NumRand[Counter} ← RandUp(0, 100) 4 Counter ← Counter + 1 5 ENDWHILE 4 2(b) Any three from: FOR Counter ← 0 TO 49 // FOR Counter ← 1 TO 50 NumRand[Counter] ← RandUp(0,100) / RandUp(-1,100) NEXT // NEXT Counter 3 (a) To earn marks, you must identify a constant name (e.g., MaxNoTables), provide its specific value (e.g., 20), and clearly state its purpose in the program (e.g., storing the maximum number of tables). (b) To earn marks, you need to describe the arrays by identifying their names, explaining their purpose, stating their length, specifying the data type they hold, explaining why multiple arrays are used, or providing sample data.

Cambridge IGCSE Computer Science · 0478

IGCSE Computer Science (0478) Programming past paper questions

Revise IGCSE Computer Science (0478) — Programming with real Cambridge past-paper questions grouped by topic, each shown with its marking scheme. Working one topic at a time targets exactly the skill each question tests.

67 free questions from 2016–2021, each with its marking scheme. Open the full topical bank to filter by subtopic, paper, and year.