from linked_list import LinkedList
from detect_cycle import detect_cycle

def find_pos(head, node):
	pos = -1
	temp = head
	if node == None:
		return pos
	while temp != node:
		pos = pos + 1
		temp = temp.next
	return pos+1

def find_length(head):
	length = 0
	temp = head
	while temp != None:
		length = length + 1
		temp = temp.next
	return length

def find_tail(head):
	temp = head
	for i in range(find_length(head) - 1):
		temp = temp.next
	return temp

def main(input_1,input_2):
	linked_list = LinkedList()
	linked_list.create_linked_list(input_1)
	if input_2 != -1:
		temp = linked_list.head
		for i in range(input_2):
			temp = temp.next
		tail = find_tail(linked_list.head)
		tail.next = temp

	return detect_cycle(linked_list.head)