Arrays

• array: list data structure in which elements are stored in adjacent memory addresses
• arrays support direcrt access since it’s possible to mathematically calculate the address of a particular element
• you have to declare how big your array should be before you can use it
• it’s difficult to insert values into the middle of an array because elements need to be shifted along
• array elements are accessed using subscript notation eg NUM[2] = 98
• their structure lends itself to processing using loops

Linked Lists

• constructing a linked list
• types of linked list
• sketching linked list insertion
• linked list methods

Arrays vs Linked Lists

• arrays
  • support direct access
  • static so you have to declare how many elements you want before you use it
  • if you declare too many and don’t use them, you waste memory
  • if you don’t declare enough then you have to create an entire new array and copy elements across
  • adding and deleting elements from middle of array is problematic since existing elements need to be shifted
• linked lists
  • only support sequential access since they only have a pointer to the head node
  • dynamic meaning you don’t need to declare size
  • never waste memory ebcause only contian nodes that have data in
  • easy to insert and delete from middle of linked list

Stacks

• stack: special type of list in which you can only add and remove items from one end