Unit 11 Programming Techniques

Question 1

What is an IDE?

Answer 1

Integrated Development Environment
A software which enables you to enter, edit, compile, interpret and run your programs

Question 2

How can an IDE make entering program code as easy and quick as possible? (4)

Answer 2

• Add line numbers
• Automatically indent code
• Auto-complete commands
• Comment or un-comment a region

Question 3

What is an Algorithm?

Answer 3

A sequence of instructions that can be followed to solve a problem

Question 4

What is Pseudocode?

Answer 4

A type of instructions that are somewhere between English and a programming language

Question 5

What is an Identifier?

Answer 5

A name that points to memory location

Question 6

What is Assignment?

Answer 6

Assigning a value to the memory location

Question 7

What is the difference between a Variable and a Constant?

Answer 7

A variable can be changed a constant can’t

Question 8

Why would someone use a Constant instead of a Variable?

Answer 8

Reduces the risk of errors by reducing access to the memory location

Question 9

What does MOD do?

Answer 9

Outputs the remainder after dividing 2 numbers

Question 10

What does DIV do?

Answer 10

Outputs the integer answer after dividing 2 numbers

Question 11

What does a Boolean Condition evaluate to?

Answer 11

True or Flase

Question 12

What does AND do?

Answer 12

Returns TRUE if both conditions are true

Question 13

What does OR do?

Answer 13

Returns TRUE if either of the conditions is true

Question 14

What does NOT do?

Answer 14

A TRUE expression becomes FALSE and vice versa

Question 15

What is Iteration?

Answer 15

Repetition of sections of code. There are 3 types of loop: While, Do and For

Question 16

What is a Subroutine?

Answer 16

A set of instructions with a name. Program flow will ‘jump’ to that subroutine when called. When the subroutine has finished, the program will continue from where it was called

Question 17

What is a Library Subroutine?

Answer 17

A subroutine that comes pre-defined with the programming language

Question 18

How do you pass data to a Subroutine?

Answer 18

Put arguments in parentheses after calling the subroutine

Question 19

Why is the order of the parameters in the parentheses in the Subroutine important?

Answer 19

Each parameter order corresponds to a different variable in the subroutine

Question 20

How can a Function return a value?

Answer 20

Using a return statement

Question 21

What’s the difference between a Local and Global Variable?

Answer 21

A local variable is contained in a subroutine and can only be used, referenced or changed in that subroutine. A global variable is defined in the main program and can be used in any subroutine called from the main program

Question 22

What are the advantages of a Local Variable? (2)

Answer 22

• The subroutines will be independent of a particular program and can be re-used in different programs
• There is no chance of accidentally changing a variable in the main program that is used in a subroutine or vice versa

Question 23

What is Modular Programming?

Answer 23

Where a major task is broken down into smaller subtasks that may be further broken down until each ‘module’ performs a single function

Question 24

What are the advantages of Modular Programming? (4)

Answer 24

• Large programs are broken down into subtasks that are easier to program and manage
• Each module can be individually tested
• Modules can be re-used several times in a program
• Large programs are much easier to debug and maintain

Question 25

What are the essential characteristics of a Recursive Routine? (3)

Answer 25

• A stopping condition or base case must be included
• For input values other than the stopping condition, the routine must call itself
• The stopping condition must be reached after a finite number of calls

Question 26

What is the Fibonacci Sequence?

Answer 26

Where each number is found by adding the two preceding numbers

Question 27

In OOP what does a class do?

Answer 27

Defines what an object in the class will look like (its properties), and what it can do (its methods). Its the blueprint for an object

Question 28

In OOP what is an Attribute?

Answer 28

A property of an object

Question 29

In OOP what is a Method?

Answer 29

The procedures that an object can perform

Question 30

Are Attributes normally defined as public or private?

Answer 30

Private

Question 31

Are Methods normally declared as public or private?

Answer 31

Public

Question 32

What does Encapsulation do?

Answer 32

Wraps the attributes and methods in the class definition, hiding details of the implementation from the user

Question 33

What is a Constructor?

Answer 33

A method used to create a new object in a class

Question 34

What is Instantiation?

Answer 34

Creating an instance of an object

Question 35

What is Polymorphism?

Answer 35

The ability of a programming language to process objects differently depending on their class

Question 36

What are the advantages of OOP? (4)

Answer 36

• Classes can easily be saved in a library and reused in other programs
• Encapsulation reduces code complexity
• Attributes can be hidden from users so that they cannot change them accidentally
• Easier to modify and maintain