Stacks

Question 1

In what order are items added to and removed from a stack?

Answer 1

Last in - first out (LIFO)

Question 2

List the functions of these following operations:
- Create
- Delete
- Push
- Pop
- Peek
- isEmpty
- isFull
- currentSize

Answer 2

• Create a new stack object
• Delete a stack object
• Push an element to the top of a stack
• Pop an element from the top of a stack
• Peek the value of the top element, leaving the stack unchanged
• isEmpty to check if the stack is currently empty
• isFull to check if the stack is currently full
• currentSize a useful operation to report how many items present

Question 3

How are Stacks useful for recursion?

Answer 3

The operating system uses a stacks to control memory during recursive processes (adds new processed to top of stack, giving them priority)