Question

PROBLEM- void CBQueue::printF2B( ) If the queue is empty, the method should print “Queue is empty”, otherwise, this method should print the items in the queue starting at the front of the queue and proceeding to the rear of the queue. The items should be printed one per line. Now that this method is written, you can do a more thorough job of testing enqueue( ). You will want to call printF2B( ) and printB2F( ) after implementing each method to test to make sure all of your pointers are setup correctly.

EXISTING CODE:

CBQueue.h

#include <string> // this allows you to declare and use strings

#include <iostream>

using namespace std;

struct qNode

{

  string data;

  qNode* next;

  qNode* prev;

};

class CBQueue

{

  public:

    CBQueue();

int CBQueue::getSize( );

bool CBQueue::isEmpty( );

  private:

    qNode* front;

    qNode* rear;

    int size;

};

#include "CBQueue.h"

CBQueue::CBQueue()

{

front = NULL;

rear = NULL;

size = 0;

}

//Returns elements in CBQuene

int CBQueue::getSize( ){

return size;

}

//return whether the queue is empty or not

bool CBQueue::isEmpty( ){

if(front == NULL)}{

return true;

}

else{

return false;

}

void CBQueue::enqueue(string s){

struct qNode * temp = (struct qNode *)malloc(sizeof(struct qNode));
temp->data = s;
temp->prev = NULL;
temp->next = NULL;

if (front == NULL)

{

front = rear = temp;

}

else

{

rear->next = temp;
temp->prev = rear;

rear = temp;

}

void CBQueue::printF2B( ){

}

Answer 1

void CBQueue::printF2B( ){
  temp = front;
if ((front == NULL) && (rear == NULL)) {
cout<<"Queue is empty."<<endl;
return;
}
cout<<"Queue elements are (Front to Rear): ";
while (temp != NULL) {
cout<<temp->data<<" ";
temp = temp->next;
}
cout<<endl;
}

This will do the job for you. Make sure to hit a like. :)