Teach with us

Move last element to front of a given Linked List in C++

C++Server Side ProgrammingProgramming

Given a linked list, we have to move the last element to the front. Let's see an example.

Input

1 -> 2 -> 3 -> 4 -> 5 -> NULL

Output

5 -> 1 -> 2 -> 3 -> 4 -> NULL

Algorithm

  • Initialise the linked list.

  • Return if the linked list is empty or it has single node.

  • Find the last node and second last nodes of the linked list.

  • Make the last node as new head.

  • Update the link of second last node.

Implementation

Following is the implementation of the above algorithm in C++

#include <bits/stdc++.h>
using namespace std;
struct Node {
   int data;
   struct Node* next;
};
void moveFirstNodeToEnd(struct Node** head) {
   if (*head == NULL || (*head)->next == NULL) {
      return;
   }
   struct Node* secondLastNode = *head;
   struct Node* lastNode = *head;
   while (lastNode->next != NULL) {
      secondLastNode = lastNode;
      lastNode = lastNode->next;
   }
   secondLastNode->next = NULL;
   lastNode->next = *head;
   *head = lastNode;
}
void addNewNode(struct Node** head, int new_data) {
   struct Node* newNode = new Node;
   newNode->data = new_data;
   newNode->next = *head;
   *head = newNode;
}
void printLinkedList(struct Node* node) {
   while (node != NULL) {
      cout << node->data << "->";
      node = node->next;
   }
   cout << "NULL" << endl;
}
int main() {
   struct Node* head = NULL;
   addNewNode(&head, 1);
   addNewNode(&head, 2);
   addNewNode(&head, 3);
   addNewNode(&head, 4);
   addNewNode(&head, 5);
   addNewNode(&head, 6);
   addNewNode(&head, 7);
   addNewNode(&head, 8);
   addNewNode(&head, 9);
   moveFirstNodeToEnd(&head);
   printLinkedList(head);
   return 0;
}

Output

If you run the above code, then you will get the following result.

1->9->8->7->6->5->4->3->2->NULL
raja
Hafeezul Kareem
Updated on 25-Oct-2021 05:21:53

Previous Page Print Page Next Page  
Advertisements