48. AQA GCSE (8525) SLR8 – 3.2 Introduction to subroutines

What is a subroutine?

• A debugging tool

• A type of programming language

• A block of code with a unique identifiable name within a program

• A unique identifiable name within a program

Answer explanation

A subroutine is a block of code with a unique identifiable name within a program, allowing for modular and reusable code segments.

Why are subroutines used?

• To make programs run faster

• To increase the size of the code

• To break down a big problem into smaller, manageable problems

• To make the program harder to test

Answer explanation

Subroutines are used to break down a big problem into smaller, manageable problems, making the code more organized and easier to maintain.

What are the benefits of using subroutines?

• Makes it easier to code, test, debug, and reuse code

• Increases the need to duplicate code

• Slows down development

• Makes the code harder to maintain

Answer explanation

Using subroutines makes it easier to code, test, debug, and reuse code, leading to more efficient development processes.

How can you identify a subroutine in a program?

• By the comments within the code

• By the number of lines in the code

• By the use of keywords 'procedure' or 'function'

• By the program's title

Answer explanation

The correct way to identify a subroutine in a program is by the use of keywords 'procedure' or 'function'. These keywords indicate the presence of a separate block of code that can be called upon.

What is a procedure call?

• A method to end the program

• A call to another procedure within a program

• A type of error in programming

• A request to access a website

Answer explanation

A procedure call is a call to another procedure within a program, allowing the program to execute the code within that procedure.

What happens when a subroutine is called?

• The program pauses for user input

• The program ends

• The program jumps to the code inside the subroutine and executes it

• The program deletes the subroutine

Answer explanation

When a subroutine is called, the program jumps to the code inside the subroutine and executes it, then returns to the point where the subroutine was called.

What is typically contained in the main program when using subroutines?

• Only variable declarations

• Some logic and calls to subroutines

• Only comments

• All the code of the program

Answer explanation

The main program when using subroutines typically contains some logic and calls to subroutines, not just variable declarations or comments.

What is the difference between a procedure and a function?

• There is no difference

• A procedure returns a value, while a function does not

• Functions are used only in specific programming languages

• A function returns a value, while a procedure does not

Answer explanation

A function returns a value, while a procedure does not

What should a subroutine be designed to do?

• Make the program run slower

• Cause errors in the program

• Perform one task or action

• Perform multiple tasks at once

Answer explanation

A subroutine should be designed to perform one task or action, not multiple tasks at once. This helps in maintaining code clarity and organization.

How does using subroutines affect code maintenance?

• Makes it more difficult

• Has no effect

• Makes it easier

• Is only beneficial for small programs

Answer explanation

Using subroutines makes code maintenance easier by promoting code reusability, reducing redundancy, and allowing for easier debugging and updates.