Allows developer to use same code in more than one place
Declared then saved in libraries/headers
Library functions
Library functions can be included into your code and can be call at anytime
Creating Functions
Definition
called after the main function
Anatomy
data/return type
data type that will be returned by the function
function name
arguments/parameters
input given to the function
body / implementation
tells code what to do
Return statement
ending point of the function
Prototype
called before the main function
Default arguments
allows for a “default value” to be used if no parameters are provided
implemented by setting parameters equal to a value in definition
Overloaded Functions
allows a developer to define multiple function to the same name
each function should have different parameters
the compiler will know which function is being called because of the parameters
Template functions
allows functions to return diffrent types of data
uses a “typename” as a placeholder for the alctual return type
the compiler determines what “type” to use
Recursive functions
A function that calls itself in its body
will continue to cal untill some condition is met
the “base case” of the function occurse once this occurs
Arrays
What is an array
holds items of a data type in a contiguous memory
use array class template
unlike vectors, the size is constant
to define an array you must
‘std::array<type, arraySize> arrayName;’
Interacting with an array
you can assign an element of an array like a normal variable
a[2]=3;
access elements like a normal varibable
std::cout<<a[2];
this prints 3
to make them somewhat understading of their bounds use a.a prefix
to know about their own size
std::cout<<a.size();
this prints 4 telling how big is the array
elements are not implicitly zero
Filling an array with a loop
If you tried to index past bounds (ie. a[152]) this would throw an exception (be an error) ● size_t is a data type used to represent the size of any object
