Chapter 21, Problem 3SA

Explanation of Solution

Stack:

• A stack is a linear data structure.
• It follows the order FILO (first in last out) or LIFO (last-in-first-out) for operations.
• The two main operations performed in a stack are,
  • Push() – Add item to stack.
  • Pop() – Remove item from stack.
• The stack is a container used to store objects which are added and removed in last-in-first-out (LIFO) or first-in-last-out (FILO) fashion.
• The stack will have only one end for adding and removing items.
  • So, when the method pop is called on a stack, it removes item which is added recently on the stack...