C++ Program to Implement Queue using Linked List

This C++ program, using iteration, implements the list of elements removed from the queue in first in first out mode using a linked list. A linked list is an ordered set of data elements, each containing a link to its successor.

Here is the source code of the C program to display the list of elements removed from the queue. The C++ program is successfully compiled and run on DevCpp, a C++ compiler. The program output is also shown below.

  1. /*
  2.  * C++ Program to Implement Queue using Linked List
  3.  */
  4. #include<iostream>
  5. #include<stdio.h>
  6. #include<conio.h>
  7. using namespace std;
  8. struct node
  9. {
  10.     int data;
  11.     node *next;
  12. }*front = NULL,*rear = NULL,*p = NULL,*np = NULL;
  13. void push(int x)
  14. {
  15.     np = new node;
  16.     np->data = x;
  17.     np->next = NULL;
  18.     if(front == NULL)
  19.     {
  20.         front = rear = np;
  21.         rear->next = NULL;
  22.     }
  23.     else
  24.     {
  25.         rear->next = np;
  26.         rear = np;
  27.         rear->next = NULL;
  28.     }
  29. }
  30. int remove()
  31. {
  32.     int x;
  33.     if(front == NULL)
  34.     {
  35.         cout<<"empty queue\n";
  36.     }
  37.     else
  38.     {
  39.         p = front;
  40.         x = p->data;
  41.         front = front->next;
  42.         delete(p);
  43.         return(x);
  44.     }
  45. }
  46. int main()
  47. {
  48.     int n,c = 0,x;
  49.     cout<<"Enter the number of values to be pushed into queue\n";
  50.     cin>>n;
  51.     while (c < n)
  52.     {
  53. 	cout<<"Enter the value to be entered into queue\n";
  54. 	cin>>x;
  55.         push(x);
  56.         c++;
  57.      }
  58.      cout<<"\n\nRemoved Values\n\n";
  59.      while(true)
  60.      {
  61.         if (front != NULL)
  62.             cout<<remove()<<endl;
  63.         else
  64.             break;
  65.      }
  66.      getch();
  67. }

Output
Enter the number of values to be pushed into queue
6
Enter the value to be entered into queue
5
Enter the value to be entered into queue
4
Enter the value to be entered into queue
3
Enter the value to be entered into queue
2
Enter the value to be entered into queue
1
Enter the value to be entered into queue
0
 
 
Removed Values
 
5
4
3
2
1
0

Sanfoundry Global Education & Learning Series – 1000 C++ Programs.

advertisement
If you wish to look at all C++ Programming examples, go to C++ Programs.

advertisement
Subscribe to our Newsletters (Subject-wise). Participate in the Sanfoundry Certification to get free Certificate of Merit. Join our social networks below and stay updated with latest contests, videos, internships and jobs!

Youtube | Telegram | LinkedIn | Instagram | Facebook | Twitter | Pinterest
Manish Bhojasia - Founder & CTO at Sanfoundry
I’m Manish - Founder and CTO at Sanfoundry. I’ve been working in tech for over 25 years, with deep focus on Linux kernel, SAN technologies, Advanced C, Full Stack and Scalable website designs.

You can connect with me on LinkedIn, watch my Youtube Masterclasses, or join my Telegram tech discussions.

If you’re in your 20s–40s and exploring new directions in your career, I also offer mentoring. Learn more here.