Java Program For Removing Every K-th Node Of The Linked List

// Java program to delete every k-th 
// Node of a singly linked list.
class GFG{

// Linked list Node 
static class Node
{
    int data;
    Node next;
}

// To remove complete list (Needed 
// for case when k is 1)
static Node freeList(Node node)
{
    while (node != null)
    {
        Node next = node.next;
        node = next;
    }
    return node;
}

// Deletes every k-th node and 
// returns head of modified list.
static Node deleteKthNode(Node head, 
                          int k)
{
    // If linked list is empty
    if (head == null)
        return null;

    if (k == 1)
    {
        head = freeList(head);
        return null;
    }

    // Initialize ptr and prev before 
    // starting traversal.
    Node ptr = head, prev = null;

    // Traverse list and delete 
    // every k-th node
    int count = 0;
    while (ptr != null)
    {
        // Increment Node count
        count++;

        // Check if count is equal to k
        // if yes, then delete current Node
        if (k == count)
        {
            // Put the next of current Node in
            // the next of previous Node
            prev.next = ptr.next;

            // Set count = 0 to reach further
            // k-th Node
            count = 0;
        }

        // Update prev if count is not 0
        if (count != 0)
            prev = ptr;

        ptr = prev.next;
    }
    return head;
}

// Function to print linked list 
static void displayList(Node head)
{
    Node temp = head;
    while (temp != null)
    {
        System.out.print(temp.data + 
                         " ");
        temp = temp.next;
    }
}

// Utility function to create a 
// new node.
static Node newNode(int x)
{
    Node temp = new Node();
    temp.data = x;
    temp.next = null;
    return temp;
}

// Driver Code
public static void main(String args[])
{
    // Start with the empty list 
    Node head = newNode(1);
    head.next = newNode(2);
    head.next.next = newNode(3);
    head.next.next.next = newNode(4);
    head.next.next.next.next = 
    newNode(5);
    head.next.next.next.next.next = 
    newNode(6);
    head.next.next.next.next.next.next =
    newNode(7);
    head.next.next.next.next.next.next.next =
    newNode(8);

    int k = 3;
    head = deleteKthNode(head, k);

    displayList(head);
}
}
// This code is contributed by Arnab Kundu