A-LevelComputer ScienceData types and structures9618/22 · May/June 2024 · Q39 Marks

A factory needs a program to help manage its production of items. Data will be stored about each item. The data for each item will be held in a record structure of type Component. The programmer has started to define the fields that will be needed as shown in the table. | Field | Example value | Comment | |----------|---------------|-------------------------------------------------| | Item_Num | 123478 | a numeric value used as an array index | | Reject | FALSE | TRUE if this item has been rejected | | Stage | 'B' | a letter to indicate the stage of production | | Limit_1 | 13.5 | any value in the range 0 to 100 inclusive | | Limit_2 | 26.4 | any value in the range 0 to 100 inclusive |

(a)(i)Write pseudocode to declare the record structure for type Component.[4]
(a)(ii)A 1D array Item of 2000 elements will store the data for all items. Write pseudocode to declare the Item array.[2]
(b)State three benefits of using an array of records to store the data for all items.[3]

Mark scheme

Marking points from the official mark scheme (May/June 2024). The mark or mark type is shown in brackets.

[4] Mark as follows:
1 One mark for TYPE and ENDTYPE statements
2 One mark for Item_Num and Reject fields
3 One mark for Stage field
4 One mark for Limit fields as REAL
[2] One mark per underlined phrase
DECLARE Item : ARRAY [1:2000] OF Component//
DECLARE Item : ARRAY [2000] OF Component//
DECLARE Item : ARRAY [0:1999] OF Component
[3] One mark per point:
1 Allows for iteration / can use a loop to access the records / data items
2 Use of index to directly access a record in the array // Example of simplification of code e.g. use of dot notation Item[1].Stage
3 Simplifies the code / algorithm // Reduces duplication of code // Program easier to write / understand / maintain / test / debug // Data items/record easier to search / sort / manipulate

On Oracle Prep you can write or photograph your own answer and have it marked by AI against this mark scheme, with feedback on what you missed.