MODULE 2: Stack

Prelim Topic

Stack

• A stack is a way to group things together by placing one thing on top of another and then removing things one at a time from the top of the stack.

Stack

• In computer science, a stack is a Last-in, First-Out (L I F O) abstract data type and data structure. A stack can have any abstract data type as an element but is characterized by only two fundamental operations: push and pop.

push()

(Basic Operations on Stack)

• To insert an element into the stack

pop()

(Basic Operations on Stack)

• To remove an element from the stack

top()

(Basic Operations on Stack)

• Returns the top element of the stack

isEmpty()

(Basic Operations on Stack)

• returns true if the stack is empty, if not, false

Size()

(Basic Operations on Stack)

• Returns the size of the stack

peek()

(Basic Operations on Stack)

• Is a method that looks at the item at the top of the stack

search()

(Basic Operations on Stack)

• Is a method that returns the position (in number) of an item from the top of a stack