C++ Linked List Exercises: Reverse doubly linked list
C++ Linked List: Exercise-16 with Solution
Write a C++ program to create a doubly linked list of n nodes and display it in reverse order.
Test Data:
Doubly linked list is as follows:
Traversal in Forward direction:
Orange White Green Red
Traversal in Reverse direction:
Red Green White Orange
Reverse Doubly linked list:
Traversal in Forward direction:
Red Green White Orange
Traversal in Reverse direction:
Orange White Green Red
Sample Solution:
C++ Code:
#include <iostream>
using namespace std;
// A doubly linked list node
struct Node {
string data;
struct Node* next;
struct Node* prev;
};
//Append node at the front of the list
void append_data(Node** head, string new_data)
{
//Create a new node and allocate memory.
struct Node* newNode = new Node;
//assign data to new node
newNode->data = new_data;
// A new node has been added with the name head and the previous node
// set to null, since it is being added at the front.
newNode->next = (*head);
newNode->prev = NULL;
//previous head is new node
if ((*head) != NULL)
(*head)->prev = newNode;
//head points to new node
(*head) = newNode;
}
void reverse(Node** head)
{
struct Node* tmp = NULL;
struct Node* currNode = *head;
while (currNode != NULL) {
//Swap this node’s next and prev references
tmp = currNode->prev;
currNode->prev = currNode->next;
currNode->next = tmp;
//The next node is now the prev node because of swap
currNode = currNode->prev;
}
if (tmp != NULL)
*head = tmp->prev;
}
// Following function display contents of the doubly linked list
void displayDlList(Node* head)
{
Node* last_node;
cout << "\n\nTraversal in Forward direction:\n";
while (head != NULL) {
cout << " " << head->data << " ";
last_node = head;
head = head->next;
}
cout << "\nTraversal in Reverse direction:\n";
while (last_node != NULL) {
cout << " " << last_node->data << " ";
last_node = last_node->prev;
}
}
//main program
int main() {
/* Start with the empty list */
struct Node* head = NULL;
append_data(&head, "Red");
append_data(&head, "Green");
append_data(&head, "White");
append_data(&head, "Orange");
cout<<"Doubly linked list is as follows: ";
displayDlList(head);
reverse(&head);
cout<<"\n\nReverse Doubly linked list: ";
displayDlList(head);
return 0;
}
Sample Output:
Doubly linked list is as follows: Traversal in Forward direction: Orange White Green Red Traversal in Reverse direction: Red Green White Orange Reverse Doubly linked list: Traversal in Forward direction: Red Green White Orange Traversal in Reverse direction: Orange White Green Red
Flowchart:


CPP Code Editor:
Contribute your code and comments through Disqus.
Previous C++ Exercise: Create and display a doubly linked list.
Next C++ Exercise: Count number of nodes in a doubly linked list.
What is the difficulty level of this exercise?
C++ Programming: Tips of the Day
How to Use CCache with CMake?
This directory contains loads of symlinks for every possible name the compiler could be called from (like gcc and gcc-4.3), all pointing to ccache.
And I didn't even create the symlinks. That directory comes pre-filled when I install ccache on Debian.
Ref: https://bit.ly/3KoJN3g
- Weekly Trends
- Python Interview Questions and Answers: Comprehensive Guide
- Scala Exercises, Practice, Solution
- Kotlin Exercises practice with solution
- MongoDB Exercises, Practice, Solution
- SQL Exercises, Practice, Solution - JOINS
- Java Basic Programming Exercises
- SQL Subqueries
- Adventureworks Database Exercises
- C# Sharp Basic Exercises
- SQL COUNT() with distinct
- JavaScript String Exercises
- JavaScript HTML Form Validation
- Java Collection Exercises
- SQL COUNT() function
- SQL Inner Join
We are closing our Disqus commenting system for some maintenanace issues. You may write to us at reach[at]yahoo[dot]com or visit us at Facebook