1.2.4 types of programming languages

Question 1

what are programming paradigms

Answer 1

Different approaches to using a programming language to solve problems.

Question 2

which two broad categories are programming paradigms split into

Answer 2

-imperative
-declarative

Question 3

Imperative programming paradigms

Answer 3

uses code that clearly specifies the actions to be
performed

Question 4

Declarative programming paradigms

Answer 4

focuses on stating the desired result rather than the exact series of instructions that need to be performed to get to the result. . It is the role of the programming language to determine how best to obtain the result and the details about how it is obtained are abstracted from the user.

Question 5

Advantages of procedural programming

Answer 5

-can be applied to a wide range of problems
- relatively easy to write and interpret

Question 6

procedural programming

Answer 6

This is a type of imperative programming which uses a sequence of
instructions which may be contained within procedures. These instructions are carried out in a step-by-step manner.

Question 7

state a use of declarative programming

Answer 7

-Artificial intelligence
-expert systems/knowledge based systems

Question 8

identify the 4 main structures used in structural programming

Answer 8

-sequence
-selection
-iteration
-recursion

Question 9

Sequence

Answer 9

Code is executed line-by-line, from top to bottom.

Question 10

Selection

Answer 10

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

Question 11

Iteration

Answer 11

A block of code is executed a certain number of times or while a condition is met. Iteration uses FOR, WHILE or REPEAT UNTIL loops.

Question 12

Recursion

Answer 12

Functions are expressed in terms of themselves. Functions are executed, calling themselves, until a certain condition known as a base case (which does not call the function) is met.

Question 13

what is procedural programming suited for

Answer 13

suited to problems that can easily be expressed as a series of instructions

Question 14

how does assembly language differ from machine code

Answer 14

Assembly language uses mnemonics rather than binary. One line in assembly language is equal to one line in machine code

Question 15

mnemonics

Answer 15

Question 16

state the function of opcode and operand

Answer 16

the opcode specifies the instruction to be preformed and addressing mode. The operand holds a value which is related to the data on which the instruction is to be preformed

Question 17

state 4 addressing modes

Answer 17

-immediate addressing
-direct addressing
-indirect addressing
-indexed addressing

Question 18

Immediate Addressing

Answer 18

The operand is the actual value upon which the instruction is to be performed, represented in binary. So the memory does not need to be searched to find the required value

Question 19

Direct Addressing

Answer 19

The operand gives the address which holds the value upon which the instruction is to be performed. Direct addressing is used in LMC.

Question 20

Indirect Addressing

Answer 20

The operand gives the address of a memory location which holds another address, where the data is located.

Question 21

Indexed Addressing

Answer 21

An index register is used, which stores a certain value. The address of the operand is determined by adding the operand to the index register. This is necessary to add an offset in order to access data stored contiguously in memory such as in arrays

Question 22

Advantages of oop

Answer 22

-oop allows for high level of usability which makes it useful for projects with many components

-classes can be used across multiple projects

-There is a high level of abstraction and it is not necessary for programmers to know details about how code is implemented.

-The modular structure used in OOP makes it easy to maintain and update.

-Encapsulation is a key reason for choosing OOP as it makes the code more reliable by protecting attributes from being directly accessed.

Question 23

Polymorphism

Answer 23

Ability for methods of the same name to be used in inherited classes with different behaviours exhibited

Question 24

Inheritance

Answer 24

Inheritance is when a class takes on the methods and attributes of a parent class. The inheriting class may override some of these methods/attributes and may have additional extra methods and attributes of its own

Question 25

Class

Answer 25

A template defining methods and attributes used to make objects

Question 26

Encapsulation

Answer 26

The hiding of the implementation of a class and controlling access to its methods and attributes

Question 27

Object

Answer 27

An object is an instance of a class

Question 28

disadvantages of OOP

Answer 28

• This is a different style of programming and so requires an alternative style of thinking. This can be difficult for programmers accustomed to other paradigms to pick up.
• OOP is not suited to all types of problems. Where few components are reused, OOP may in fact result in a longer, more inefficient program.
• Generally unsuitable for smaller problems.

Question 29

overriding

Answer 29

Overriding is redefining a method within a subclass and altering the code so that it functions differently and produces a different output.

Question 30

Overloading

Answer 30

Overloading is passing in different parameters into a method. Both of these forms of polymorphism would produce different results which would depend on the scenario

Question 31

Assembly language

Answer 31

Assembly language is the next level up from machine code
and is part of a family of low level languages. This is converted to machine code using an assembler when it is executed. Assembly language uses mnemonics rather than binary, which makes it easier to use than direct machine code.

Question 32

getter and setters

Answer 32

● A setter is a method that sets the value of a particular attribute
● A getter is another special method used in OOP which retrieves the value of a given
attribute
● Getters and setters ensure attributes cannot be directly accessed and edited but
can only be altered by public methods. This is called encapsulation.
● Every class must also have a constructor method which allows a new object to be
created