Find n/k-th Node in Linked List

Problem

Given a singly linked list and a number k. Write a function to find the $(N/k)^{th}$ element, where N is the number of elements in the list. We need to consider ceil value in case of decimals.

Input:

The first line of input contains an integer T denoting the number of test cases. The first line of each test case consists of an integer N. The second line consists of N spaced integers.The last line consists of an integer k.

Output:

Return the data value of (N/k)th node in the Linked List.

Your task:

The task is to complete the function fractional_node() which should find the n/kth node in the linked list and return its data value.

Constraints:

• $1 <= T <= 100$
• $1 <= N <= 100$
• $K > 0$

Solution

Python

def fractionalNodes(head,k):
    if (k <= 0 or head == None):
        return None
    fractionalNode = None
    i = 0
    temp = head
    while (temp != None):
        if (i % k == 0):
            if (fractionalNode == None):
                fractionalNode = head
            else:
                fractionalNode = fractionalNode.next
        i = i + 1
        temp = temp.next
    return fractionalNode.data

Java

public static int nknode(Node head, int k) {
   if (k <= 0 || head == null)
        return -1;
    Node fractionalNode = null;
    int i = 0;
    Node temp = head;
    while (temp != null) {
        if (i % k == 0) {
            if (fractionalNode == null) {
                fractionalNode = head;
            } else {
                fractionalNode = fractionalNode.next;
            }
        }
        i++;
        temp = temp.next;
    }
    if (fractionalNode != null) {
        return fractionalNode.data;
    } 
    else {
        return -1; 
    }
}

C++

int fractional_node(struct Node *head, int k) {
    if (k <= 0 || head == nullptr)
        return -1;
    Node* fractionalNode = nullptr;
    int i = 0;
    Node* temp = head;
    while (temp != nullptr) {
        if (i % k == 0) {
            if (fractionalNode == nullptr) {
                fractionalNode = head;
            } else {
                fractionalNode = fractionalNode->next;
            }
        }
        i++;
        temp = temp->next;
    }
    if (fractionalNode != nullptr) {
        return fractionalNode->data;
    } 
    else {
        return -1; 
    }
}

C

int fractional_node(struct Node *head, int k) {
    if (k <= 0 || head == NULL)
        return -1;
    struct Node *fractionalNode = NULL;
    int i = 0;
    struct Node *temp = head;
    while (temp != NULL) {
        if (i % k == 0) {
            if (fractionalNode == NULL) {
                fractionalNode = head;
            } else {
                fractionalNode = fractionalNode->next;
            }
        }
        i++;
        temp = temp->next;
    }
    if (fractionalNode != NULL) {
        return fractionalNode->data;
    } 
    else {
        return -1;
    }
}