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Implement Queue Using Stacks

Explore how to implement a queue using two stacks by applying push and pop stack operations. Learn two approaches that optimize either enqueue or dequeue operations, including their complexities and step-by-step pseudocode to understand stack and queue functionality.

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Statement

Given a Stack class with common operations such as push(), pop(), and isEmpty(), implement a Queue class with its enqueue(), dequeue(), and isEmpty() operations. The isEmpty() function should return true if the stack is empty and false otherwise.

Note: If the queue is empty, the dequeue() function should return −1-1.

A stack is a data structure in which objects are inserted and removed according to the LIFOLast In First Out principle, meaning the object that was most recently added to the stack is the first to be removed. There are two important functionalities of the stack:

  • push(): Inserts an item at the top of the stack.
  • pop(): Removes an item from the top of the stack and returns it.

A queue is a data structure in which objects are inserted and removed according to the FIFOFirst In First Out ...