Problem: https://www.hackerrank.com/challenges/delete-a-node-from-a-linked-list/problem

Problem Statement:
You’re given the pointer to the head node of a linked list and the position of a node to delete. Delete the node at the given 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 list may become empty after you delete the node.

Sample Code:

def deleteNode(head, position):
    if position==0:
        return head.next
    ptr=head
    c=1
    while ptr.next is not None:
        if c==position:
            ptr.next=ptr.next.next  
            break  
        ptr=ptr.next
        c+=1
    return head        
#!/bin/python3

import math
import os
import random
import re
import sys

class SinglyLinkedListNode:
    def __init__(self, node_data):
        self.data = node_data
        self.next = None

class SinglyLinkedList:
    def __init__(self):
        self.head = None
        self.tail = None

    def insert_node(self, node_data):
        node = SinglyLinkedListNode(node_data)

        if not self.head:
            self.head = node
        else:
            self.tail.next = node


        self.tail = node

def print_singly_linked_list(node, sep, fptr):
    while node:
        fptr.write(str(node.data))

        node = node.next

        if node:
            fptr.write(sep)

# Complete the deleteNode function below.

#
# For your reference:
#
# SinglyLinkedListNode:
#     int data
#     SinglyLinkedListNode next
#
#
def deleteNode(head, position):
    ####
    if position==0:
        return head.next
    ptr=head
    c=1
    while ptr.next is not None:
        if c==position:
            ptr.next=ptr.next.next  
            break  
        ptr=ptr.next
        c+=1
    return head        


if __name__ == '__main__':
    fptr = open(os.environ['OUTPUT_PATH'], 'w')

    llist_count = int(input())

    llist = SinglyLinkedList()

    for _ in range(llist_count):
        llist_item = int(input())
        llist.insert_node(llist_item)

    position = int(input())

    llist1 = deleteNode(llist.head, position)

    print_singly_linked_list(llist1, ' ', fptr)
    fptr.write('\n')

    fptr.close()

Explanation:

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