Delete a Node

Problem Statement :

Delete the node at a given position in a linked list and return a reference to the head node. The head is at position 0. The list may be empty after you delete the node. In that case, return a null value.


After removing the node at position 2, list'= 0->1->-3.

Function Description:

Complete the deleteNode function in the editor below.

deleteNode has the following parameters:
- SinglyLinkedListNode pointer llist: a reference to the head node in the list
- int position: the position of the node to remove

- SinglyLinkedListNode pointer: a reference to the head of the modified list

Input Format:

The first line of input contains an integer n, the number of elements in the linked list.
Each of the next n lines contains an integer, the node data values in order.
The last line contains an integer, position, the position of the node to delete.

     1.  1<=n<=1000
     2.  1<=list[i]<=1000

Solution :


                            Solution in C :

In C:

//the following function is all that is needed to complete
// the challenge in hackerrank platform.

SinglyLinkedListNode* deleteNode(SinglyLinkedListNode* llist, int position) {
    if((position) == 0) {
        return llist->next;
    llist->next = deleteNode(llist->next, position-1);
    return llist;

In C++:

//the following function is all that is needed to complete
//the challenge in hackerrank platform

Node* Delete(Node *head, int position)
  // Complete this method
    Node *prev = NULL;
    Node *ptr = head;
    int pos = 0;
        delete (ptr);
            delete (ptr);
    return head;

In Java:

//the following method is all that is needed to complete the 
//challenge in hackerrank plartform

static SinglyLinkedListNode deleteNode(SinglyLinkedListNode llist, int position) {
        int currentNodePosition = 0;
        SinglyLinkedListNode head = llist;
        SinglyLinkedListNode currentNode = llist;
         if (position == 0) {
            head =;
            return head;
        while (currentNodePosition < position - 1) {
            currentNode =;
        if ( != null && != null) {
        return head;

In Python 3: 

#the following method is all that is needed to complete the
#challenge in hackerrank platfrom

def Delete(head, position):
  currentPos = 0
  prevNode = None
  node = head
  while currentPos < position:
    currentPos = currentPos+1
    prevNode = node
    node =

  if prevNode is not None: =
      return head
      n = = None
      return n

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