Question

Given C++ Stack Code, Modify the code to  work like a Queue.(First in First out) 

Stack
#ifndef STACK_H
#define STACK_H

#include "Node.h"


 
 template
 class Stack {
 private:
    
     Node* top;

 public:
     // Constructor
     Stack() {
      
         top = nullptr;
     }

    
    

    
     void push(Object ab) {
         
         if (top != nullptr) {
            
             Node* newNode = new Node(ab, *top);
   
             top = newNode;
         } else {
             
             Node* newNode = new Node(ab);
            
             top = newNode;
         }
     }

     
     Object pop() {
        
         if (top != nullptr) {
             Node *returnVal = top;
            
             top = top->getNext();
             Object returnObject = returnVal->getItem();
             
             delete returnVal; 
             return returnObject;
         } else {
            
             return Object();
         }
     }

    
     bool isThere(Object a) {
         Node* Copy = top;
        
         while (Copy != nullptr) {
             if (Copy->getItem() == a) {
                 
                 return true;
             }
             
             Copy = Copy->getNext();
         }
        
         return false;
     }


    
 };


#endif //STACK_H

Answer 1

QUEUE:
#include "Node.h" 
 template
 class Queue {
 private:    
     Node* front;
     Node* rear;
 public:
     // Constructor
     Queue() {      
         front = nullptr;
         rear = nullptr;
     }
     void push(Object ab) {
         
         if (top != nullptr) {            
             Node* newNode = new Node(ab, *rear);   
             rear = newNode;
         } else {             
             Node* newNode = new Node(ab);            
             front = newNode;
             rear = newNode;
         }
     }     
     Object pop() {        
         if (front != nullptr) {
             Node *returnVal = front;            
             front = front->getNext();
             Object returnObject = returnVal->getItem();             
             delete returnVal; 
             return returnObject;
         } else {            
             return Object();
         }
     }    
     bool isThere(Object a) {
         Node* Copy = front;        
         while (Copy != nullptr) {
             if (Copy->getItem() == a) {                 
                 return true;
             }             
             Copy = Copy->getNext();
         }        
         return false;
     }    
 };