Programming techniques (2.2.1)

Question 1

What are the three main programming constructs?

Answer 1

• Sequence
• Selection
• Iteration

Question 2

What is sequence?

Answer 2

Code is execute line by line from top to bottom

Question 3

What is selection?

Answer 3

A specific block of code is run if a specific condition is met, using IF statements.

Question 4

What is iteration?

Answer 4

A block of code is executed a set number of times or while/until a condition is met using FOR, WHILE or REPEAT UNTIL loops.

Question 5

What is the scope of a variable?

Answer 5

It refers to the section of code where the variable is available.

Question 6

What are the two main variable scopes?

Answer 6

• Local

- Global

Question 7

What is a local variable?

Answer 7

A variable that can only be accessed in the block of code in which they are defined.

Question 8

Local variable ADVS

Answer 8

Ensures subroutines are self-contained i.e. the variable are not affected by code outside of the subroutine

Question 9

What is a global variable?

Answer 9

Can be accessed throughout the whole program.

Question 10

Global variable ADVS

Answer 10

Useful for values that need to be used by multiple parts of the program

Question 11

Global variable DISADVS

Answer 11

• Can be unintentionally overwritten.

- Require more memory than local variables

Question 12

What is modular programming?

Answer 12

A technique used to split large, complex programs into smaller, self-contained modules.

Question 13

Modular programming ADVS

Answer 13

• Makes problems easier to understand and approach
• Can divide tasks between a team
• Simplifies testing and maintenance, can deal with each component individually
• Code is reusable

Question 14

Modular programming DISADVS

Answer 14

• Can cause complexity in simple programs

- May be challenging to keep track of function names and values

Question 15

What are functions and procedures?

Answer 15

Blocks of codes that perform a specific task

Question 16

What is the difference between a function and a procedure?

Answer 16

A function returns a value, a procedure doesn’t

Question 17

What are parameters?

Answer 17

Values that are passed into a function

Question 18

What are the two methods that can be used to pass parameters?

Answer 18

• By value

- By reference

Question 19

What is passing by value?

Answer 19

The parameter is effectively treated as a local variable:

-A copy of the variable is copied to the parameter meaning changes made do not effect the value elsewhere.

Question 20

What is passing by reference?

Answer 20

The address of the parameter is given to the subroutine so the value will be updated at the address giving a permanent change.

Question 21

What is an IDE?

Answer 21

An Integrated Development Environment is piece of software which provides a set of tools making it easier to write, develop and debug code.

Question 22

Examples of IDEs

Answer 22

IDLE, Microsoft Visual Studio, Pycharm, Eclipse

Question 23

Common IDE features

Answer 23

• Stepping
• Variable watch
• Breakpoint
• Source code editor
• Debugging tools

Question 24

What is stepping in an IDE?

Answer 24

Allows the user to monitor the effect of each line of code by executing one line at a time.

Question 25

What is variable watch in an IDE?

Answer 25

Used to observe the changes of variable contents in real time

Question 26

What is breakpoint in an IDE?

Answer 26

Allows to set a point where the program will stop (based on a condition or a specific line), this helps to pinpoint errors.

Question 27

What features does a source code editor provide in an IDE?

Answer 27

• Autocompletion
• Indentation
• Syntax highlighting
• Bracket completion