A-LevelComputer ScienceSoftware development9618/22 · May/June 2025 · Q112 Marks

Refer to the insert for the list of pseudocode functions and operators. A program is being developed to control the production line in a factory.

(a)A number of different program life cycles are available for the development of a program.
(a)(i)Explain the need for different program development life cycles.[1]
(a)(ii)Coding is a stage in a program development life cycle. State one consideration that would influence the choice of programming language.[1]
(b)The program has been in use for a number of months and adaptive maintenance is required.
(b)(i)Give three reasons why adaptive maintenance may be required.[3]
(b)(ii)As well as adaptive maintenance, other types of program maintenance may be needed. Identify one other type of program maintenance.[1]
(c)Pseudocode has been used to design modules for the program to control the production line. The table shows four valid pseudocode expressions. Complete the table by giving the data type of the evaluated expression. Expression RIGHT (MachineCode, 4) Speed * 2.5 NOT Status IS_NUM (Check) Data type[4]
(d)A global array Product is used as part of the pseudocode design being developed to control the production line. Product is used to store the number of rejected items each day. The following pseudocode statement is used to assign a value to an element of the array: Product [x, y] ← 23 The lower and upper bound values are shown in the table: Variable X Y Lower bound 0 0 Upper bound 99 9
(d)(i)State the number of dimensions of Product[1]
(d)(ii)State the total number of elements in array Product[1]
(d)(iii)Give the pseudocode declaration for the array Product[2]

Mark scheme

Marking points from the official mark scheme (May/June 2025). The mark or mark type is shown in brackets.

[1] One mark for Choice of program development cycle depends on the approach/method required to produce the program Or One mark for a factor that would influence the choice of program development cycle, e.g. • Rapid development of program/prototypes required • Need for prototypes (at an early stage) • Complexity of problem • Skills / experience of development team / programmer(s) • Budget / Time / Resources available • Size of development team • Developer / programmer can return to earlier stages / any stage • Avoidance of repeating previous stages in development of program • How much involvement clients will have • Allows the (program) requirements to be changed during program development • (Program) requirements agreed at start of development of program Max 1
[1] Which programming language would best be suited to control the production line // Which programming language would best suit the problem being solved
[3] Examples include: • Change to (production line) requirements • New technology / hardware available (to control production line) • Changes made to library modules used • Change in relevant legislation Max 3
[1] Perfective // Corrective
[4] 1 mark for each correct row Expression RIGHT (MachineCode, 4) Speed * 2.5 NOT Status IS_NUM (Check) Data type STRING REAL BOOLEAN BOOLEAN
[1] Two / 2
[1] 1000
[2] DECLARE Product : ARRAY [0:99, 0:9] OF INTEGER 1 mark for correct upper and lower bound • [0:99, 0:9 1 mark for all other parts of declaration DECLARE Product : ARRAY [0:99, 0:9] OF INTEGER