IGCSE Computer Science 0478 Paper 22, May/June 2025

A fence measuring 2 metres in height and 20 metres in length needs painting. The area of the fence needs to be calculated so that enough paint for the job is purchased. After the task is decomposed, there are three component parts: input, process and output. Three component parts and four example descriptions are shown. Draw one line from each component part to the most appropriate relevant description. Not all descriptions will be used.

A range check is used to validate that the input temperature is an integer between –100 and 0, inclusive. Suggest suitable normal, abnormal, extreme and boundary test data to test if this validation check is working correctly. Normal test data ............................................................................................................................... Abnormal test data ........................................................................................................................... Extreme test data ............................................................................................................................. Boundary test data ...........................................................................................................................

This pseudocode algorithm should allow 500 names of people and their heights to be entered and stored in two one-dimensional (1D) arrays. The name of a person and the height of that person are in the same index in both the Names[] and the Heights[] arrays. The algorithm performs as follows: • at the start, the following data is entered: ◦ name of person ◦ height of person in cm • the data is stored in the relevant arrays • the heights of the people are totalled • the shortest person is found • at the end, the following is output: ◦ name of shortest person ◦ height of shortest person ◦ average height of all 500 people. 01 DECLARE Names : ARRAY[1:500] OF REAL 02 DECLARE Heights : ARRAY[1:500] OF REAL 03 DECLARE Shortest : REAL 04 DECLARE Total : REAL 05 DECLARE Counter : INTEGER 06 DECLARE Index : INTEGER 07 Shortest ← 500 08 Index ← 0 09 Total ← 100 10 FOR Counter ← 1 TO 500 11 INPUT Names[Index] 12 INPUT Heights[Counter] 13 Total ← Counter + Heights[Counter] 14 IF Heights[Counter] < Shortest 15 THEN 16 Shortest ← Heights[Counter] 17 Index ← Counter 18 ENDIF 19 NEXT Counter 20 OUTPUT "The shortest height is ", Heights 21 OUTPUT "The shortest person is ", Names[Index] 22 OUTPUT "The average height is ", Total / 500

This pseudocode is an algorithm. DECLARE Word : STRING DECLARE V1 : INTEGER DECLARE V2 : INTEGER DECLARE Number : INTEGER DECLARE Index : INTEGER DECLARE L1 : CHAR DECLARE L2 : CHAR DECLARE Continue : BOOLEAN INPUT Number FOR Index ← 1 TO Number INPUT Word Continue ← TRUE V1 ← 1 V2 ← LENGTH(Word) WHILE Continue = TRUE AND V1 < V2 DO L1 ← SUBSTRING(Word, V1, 1) L2 ← SUBSTRING(Word, V2, 1) IF L1 <> L2 THEN Continue ← FALSE ELSE V1 ← V1 + 1 V2 ← V2 – 1 ENDIF ENDWHILE IF Continue = TRUE THEN OUTPUT "Successful" ELSE OUTPUT "NOT successful" ENDIF NEXT Index

The flowchart shows an algorithm that is used to input 50 numbers. Each number is stored in the variable Value when it is input. Any number input that is less than or equal to –20 or greater than or equal to 50 is rejected and re-input. The accepted numbers are added together as they are entered and the total and average of these numbers are output at the end of the algorithm.

A database table, CapitalCity, stores data about capital cities from around the world. Field | Description Identification | a unique identifier Name | the name of the city Country | the name of the country in which the city is located Continent | the name of the continent in which the city is located Population | the number of people living in the city Founded | the year the city was founded AverageIncome | average income of the city’s population, in $, rounded to 2 decimal places Subway | whether or not the city has an underground railway system

A program is required to allow students to calculate the volume of a number of standard three-dimensional shapes. It will use functions to allow other shapes to be added in the future. Cuboid $\text{volume}=\text{base}\times \text{depth}\times \text{height}$ Triangular prism $\text{volume}=\frac{1}{2}\times \text{base}\times \text{depth}\times \text{height}$ Sphere $\text{volume}=\frac{4}{3}\times \text{Pi}\times \text{radius}\times \text{radius}\times \text{radius}$ $\text{Pi}$ is a constant with value 3.142 Write a program that meets the following requirements: • Output a menu to ask the user for an input to indicate the shape for which a volume needs to be calculated, from the three shapes given or if they want to stop the program. The program must validate the input. • Input the data needed to calculate the volume of the chosen shape, based on the given formulae. • Create one function for each shape to calculate and return the volume using the given formulae. Each function uses the input data as parameters. • Output the volume in the main program, rounded to two decimal places. The program continues until the user inputs the stop option from the menu. You must use pseudocode or program code and add comments to explain how your code works. All variables and constants used must be declared for this algorithm. All inputs and outputs must contain suitable messages.