Insert a node at a specific position in a linked list HackerRank Solution.

You’re given the pointer to the head node of a linked list, an integer to add to the list and the position at which the integer must be inserted. Create a new node with the given integer, insert this node at the desired position and return the head node.

A position of 0 indicates head, a position of 1 indicates one node away from the head and so on. The head pointer given may be null meaning that the initial list is empty.

As an example, if your list starts as 1 -> 2 -> 3 and you want to insert a node at position 2 with data = 4 , your new list should be 1 -> 2 -> 4 -> 3 .

Function Description Complete the function insertNodeAtPosition in the editor below. It must return a reference to the head node of your finished list.

insertNodeAtPosition has the following parameters:

  • head: a SinglyLinkedListNode pointer to the head of the list
  • data: an integer value to insert as data in your new node
  • position: an integer position to insert the new node, zero based indexing

Input Format

The first line contains an integer n, the number of elements in the linked list.
Each of the next n lines contains an integer SinglyLinkedListNode[i].data.
The next line contains an integer data  denoting the data of the node that is to be inserted.
The last line contains an integer position.

Constraints

  • 1 <= n <= 1000
  • 1 <= SinglyLinkedListNode[i].data <= 1000, where SinglyLinkedListNode[i] is the i’th  element of the linked list.
  • 0 <= position <= n.

Output Format

Return a reference to the list head. Locked code prints the list for you.

Sample Input

3
16
13
7
1
2

Sample Output

16 13 1 7

Explanation

The initial linked list is 16 13 7. We have to insert  at the position  which currently has  in it. The updated linked list will be 16 13 1 7.

Code:

 static SinglyLinkedListNode insertNodeAtPosition(SinglyLinkedListNode head, int data, int position) {
         SinglyLinkedListNode node = new SinglyLinkedListNode(data);
          SinglyLinkedListNode temp = head;

          if(head == null){
              return node;
          }
         int i=0;
         while(i < position-1) {
             temp = temp.next;
             i++;
         }
         node.next = temp.next;
         temp.next = node;
         return head;


    }

Hope you guys understand the simple solution of inserting a node at tail in linked list in java.

For practicing the question link is given https://www.hackerrank.com/challenges/insert-a-node-at-a-specific-position-in-a-linked-list/problem

In next blog we will see other operations on linked list till then Bye Bye..!

Thanks for reading…!

Happy Coding..!

Thank You…!

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