Programming Elements and Constructs

Question 1

Subroutines Definition

Answer 1

A sequence of program instructions that performs a specific task, packaged as a unit

Question 2

Parameters Definition

Answer 2

Pieces of data that are passed into a subroutine in order for that subroutine to correctly function

Question 3

Why do we use subroutines?

Answer 3

• Avoid repetition (This reduces size of program, makes code easier to maintain, and removes possibility that some code is updated while others are not)
• Define a logical structure for the program

Question 4

Advantages of subroutines

Answer 4

• Breaks down complex programs to make it easier to solve
• Can be used several times within a program
• Can reduce the amount of code than needs to be written as it allows reusing of codes without having to write it again
• Divides large program into small portions to enable simultaneous work
• Easier to read with sensible subroutine labels
• Reducing the amount of repeated task lowers the risk of errors
  Easy to maintain as each subroutine can be tested separately

Question 5

Local vs Global Variables?

Answer 5

• Local can only be accessed within the subroutine while global can be accessed by any subroutine
• Local is declared within a subroutine while global is declared outside