Fundamentals of programming Flashcards
concept of a data type
defines the type of data that a variable or object can hold
user defined data types
data types created by the programmer for a specific problem
what are reference data types used for
reference data type are used as stores for memory addresses of objects created at runtime
integer
any whole number
{8, 35)
real
numbers with a decimal point and a fractional part
{2.0, 19.234)
boolean
one of two values
{true or false}
character
a letter, number or symbol in the given character set
{h, 6, $}
string
sequence of characters
{hello world !}
casting
changing the data type
sequence
all lines are executed
selection
decisions made that determines the execution
iteration
code is repeated until specified conditions are met
count control loops
exact number of iterations known
condition controlled loops
iterates dependent on condition
variables
locations in the memory containing single values
constants
identifiers with values that remain fixed with values that remain fixed during the programs execution
why use constants
ability to update
readability
compiler optimisation
modulus
remainder
12 mod 5 gives 2
quotient
how many times
17 div 5 gives 3
boolean operators
takes boolean inputs and evaluate to a boolean value
example of string handling
string subject = “Computer Science”
subject.length = 16
subject.upper = COMPUTER SCIENCE
subject.lower = compuer science
subject.substring(0,8) = Computer
exceptions
events that occur during the executions of a program that disrupts the normal flow of the programs instructions
(sometimes cant be avoided and would normally terminate the program)
exception handling
to provide an alternative code if an exception is raised (e.g. try and catch)
pointer
stores the memory address of another variable
records
data structure that groups together related data fields, allowing them to be treated as a single unit
variable declaration
process of specifying the name and data type of a variable, without assigning it a value.
constant declaration
process of assigning an unchangeable value to a variable, ensuring its value remains constant throughout the program’s execution.
assignment
process of assigning a value to a variable
subroutine and its advantages
named section of code that can be called from anywhere for a specific task
allows the same block of code to be called multiple times from different parts of a program, thus promoting efficiency and maintainability.
definite iteration
when a loop executes a predetermined number of times (e.g. for loop)
selection
allows code to be executed based on a specific condition
e.g. if statement
indefinite iteration
when a loop continues to execute until a certain condition is met (e.g.
truncation
removing the fractional part of a number, resulting in an integer value
exponentiation
raising a number to a power
Be able to explain the differences between a variable and a constant.
named storage location that can hold a value that can be changed during program execution
named storage location that holds a value that cannot be changed during program execution.
explain the advantages of using named constants.
provide meaningful names for values, enhance code readability, and make it easier to maintain and modify code in the future.
explain the advantages of using named constants.
provide meaningful names for values, enhance code readability, and make it easier to maintain and modify code in the future.
explain the advantages of using named constants.
provide meaningful names for values, enhance code readability, and make it easier to maintain and modify code in the future.
use of parameters
to pass data within programs.
local variables
exist only while the subroutine is executing
are accessible only within the subroutine.
why is it good practice to use local variables
minimizes conflicts, enhances reliability, reduces chance of data corruption
explain how a stack frame is used with subroutine calls to store:
return addresses
parameters
local variables.
Stack frames are used by computers to store return addresses, parameters and local
variables for each subroutine call that occurs during the execution of a program.
use of recursive techniques in programming languages
it solve problems by breaking them down into smaller, simpler versions of the same problem, and solving those recursively until a base case is reached.
Understand the structured approach to program design and construction.
The structured approach to program design and construction involves breaking down a program into smaller, manageable tasks, using techniques such as stepwise refinement and modular design.
explain the advantages of the structured approach.
better code organization, modularity, and easier debugging
class
defines methods and attribute fields that capture the common behaviours and characteristics of objects
object-oriented design principles:
encapsulate what varies
favour composition over inheritance
program to interfaces, not implementation.
why is the object-oriented paradigm used.
provides programs with a clear structure that makes
developing and testing programs easier for developers
also allows for
large projects to be divided among a team of developers.
how are objects created
using a constructor, implicit or explicit, and a reference to the object assigned to a reference variable of the class type
how is aggregation represented as
white diamond line
how is composition represented
black diamond line
encapsulation
data and methods are bundled together within a class, allowing for data hiding and the controlled access and manipulation of that data.
instantiation
process of creating an object of a class, allowing it to have its own unique properties and behaviours while adhering to the structure defined by the class.
when does polymorphism occur
when objects are processed differently depending on their class.
inheritance
allows one class to share the properties and
methods of another class, while having its own properties and methods too.
