[Unit 2.2] Problem Solving and Programming

Question 1

define constant

Answer 1

a label to represent a value stored in memory that cannot change while the program is running

Question 2

define variable

Answer 2

a label to represent a value stored in memory that can change while the program is running

Question 3

define casting

Answer 3

changing a value from one data type to another

Question 4

define global variables

Answer 4

can be accessed anywhere in the program. They must be stored in memory for duration of execution

Question 5

define local variables

Answer 5

can only be accessed in a certain part of the program. Usually local to a subroutine and declared within.

Question 6

Why don’t we use global variables?

Answer 6

they use a lot more memory. its harder to locate errors as global variables can be updated anywhere

Question 7

difference between implicit and explicit casting?

Answer 7

implicit there is no loss of accuracy (int->long)

Explicit there may be loss of accuracy (double->int)

Question 8

define sequence

Answer 8

program is followed one instruction after another

Question 9

define Selection

Answer 9

Decision is made based on state of Bool (if..else)(switch..case)

Question 10

define Iteration

Answer 10

repetition of a section of code using a loop

Question 11

difference between count and condition controlled loop

Answer 11

count controlled runs a set number of times

condition controlled runs till a condition is met

Question 12

difference between a pre and post check on a condition controlled loop

Answer 12

pre check - condition checked at start of loop

post check - condition checked at end of loop

Question 13

define Function

Answer 13

subprogram that usually returns a value

Question 14

define procedure

Answer 14

subprogram that performs some operation but does not return a value

Question 15

define Parameter

Answer 15

variables that the subroutine receives (variable in the sub)

Question 16

define Argument

Answer 16

variable that you pass into the subroutine (variable in the program)

Question 17

define by value parameter

Answer 17

variable is copied, changing the value in the sub doesn’t change the original value

Question 18

define by reference parameter

Answer 18

subroutine works with the original data/variable. If it changes, it stays changed

Question 19

define Recursion

Answer 19

When a subprogram calls itself.

Question 20

key features of recursion (2)

Answer 20

base condition (stop the loop)

recursion statement

Question 21

(Dis)advantages of recursion

Answer 21

Dis:
-less efficient
-uses more memory
-may overflow stack due to too many calls (crashes)
-difficult to trace

Ad:
-quicker to write
-easier to read
-some problems are naturally recursive

Question 22

Features of IDE (9)

Answer 22

syntax highlighting

code editors

debugging tools

RTE

version control

automatic line numbers

keyword highlighting

automatic formatting

autocomplete

Question 23

define syntax highlighting

Answer 23

checks and highlights syntax errors

Question 24

define code editors

Answer 24

write and edit code

Question 25

define debugging tools

Answer 25

tools help you find errors

Question 26

define Run time environment

Answer 26

runs program, converting source code into machine code, executed by CPU

Question 27

define Version control

Answer 27

records changes, allowing you to roll back to previous version if you make major mistake

Question 28

define automatic line numbering

Answer 28

provides line numbers in margin of your code

Question 29

define keyword highlighting

Answer 29

colours applied to code as you write

Question 30

define automatic formatting

Answer 30

formats code for readability (e.g. indentations)

Question 31

define autocomplete

Answer 31

tries to predict what programmer wants

Question 32

define Iterative testing

Answer 32

during development of program

Question 33

define Final testing

Answer 33

after program is completed

Question 34

Types of test data

Answer 34

normal boundary Invalid erroneous

Question 35

What is erroneous test data

Answer 35

out of the bounds of validation, should not be accepted

Question 36

What is invalid test data

Answer 36

data of the wrong data type, should not be accepted

Question 37

What is boundary test data?

Answer 37

data at the limit of acceptability, should be accepted

Question 38

What is abstraction in terms of OOP

Answer 38

objects only reveal internal mechanisms relevant for other objects. Hiding unnecessary code

Question 39

What is encapsulation in terms of OOP

Answer 39

objects do not have access to this class nor authority to change. but can call public functions.

Question 40

what is inheritance in terms of OOP

Answer 40

objects with slight differences share code. child class inherit from parent class

Question 41

what is polymorphism in terms of OOP

Answer 41

subroutines are flexible, depending on object.

Question 42

what is instantiation in terms of OOP

Answer 42

creating an object from a class

Question 43

what is a constructor

Answer 43

method that runs when class is used to create a new object

Question 44

what is "public" in terms of OOP

Answer 44

attributes and methods that can be accessed outside the class

Question 45

what is "private" in terms of OOP

Answer 45

attributes and methods that are not accessible outside the class (allows for encapsulation)

Question 46

define "programming paradigm"

Answer 46

programming style used to create computer programs

Question 47

what is the difference between procedural & OOP

Answer 47

OOP groups values together and subroutines as objects Procedural does not link values together