Data Structures Pt.2

Data Structures Pt.2

1. Stacks

   • A Last in First Out Structure ( LIFO ). It only has one pointer called the Top. If the pointer is at position zero in the array the stack is empty.
   • When adding items, The TOP Pointer points to the position where an item is to be added.
     • The Top pointer now points to the next position where an item is to be added.
   • When removing items, the Top Pointer now moves down a position.
     • If the Top Pointer is at zero and something is trying to be removed, it will report an error and stop.

2. Binary Trees

   • A Binary Tree is a data structure that contains items in alphabetic or numeric order.
   • Each item in the tree has its data and a left and right pointer.
   • The items are called nodes. Terminal nodes are at the end indicated by -1,-1 Pointers. The first item is known as the root node.

3. Queues

   • A Queue is a First in First Out Structure ( FIFO ). A Queue has two pointers called Head and Tail.
   • Items added at the Tail Pointer. Items removed from the Head Pointer.
   • A Queue is empty when both pointers are pointing to the same position in the array.

4. Linked Lists

   • A Dynamic Data Structure
   • They are made up of nodes, with each node linked to the next node in the list.
   • They can grow to whatever size is required and their size isn't set when they are declared.