Data types, records, arrays and file handling

Learning objectives

Select an appropriate data type — integer, real, char, string, Boolean or date — for a given item of data, and state the storage and the operations each type supports

Declare and use a record type that groups related fields of different types, and read and write individual fields of a record variable

Declare, populate and traverse one-dimensional and two-dimensional arrays, and use nested loops to process every element of a two-dimensional array by row and by column

Write algorithms that read a text file line by line and write to one, opening the file in read, write or append mode and closing it when processing is finished

(A Level) Define a user-defined non-composite type such as an enumerated type or a pointer, and explain a situation in which each is the right choice

(A Level) Compare serial, sequential, random and indexed sequential file organisation, describe direct access using a hashing algorithm, and explain how a collision is resolved

(A Level) Declare and work with composite user-defined types — a set, a record and a class — and decide which user-defined type a problem calls for and write its definition