[7급 국가직 자료구조론 2025년 16번]

다음 파이썬 프로그램의 실행 결과는?

class Node:
	def __init__(self, data, next):
		self.data = data
		self.next = next
class SinglyLinkedList:
	def __init__(self):
		self.head = None
	def func1(self, data):
		node = self.head
		self.head = Node(data, node)
	def func2(self, data):
		if self.head is None: self.func1(data)
		else :
			node = self.head
			while node.next is not None: node = node.next
			node.next = Node(data, None)
	def func3(self, pos): 
		if pos < 0: return None
		node = self.head
		while pos > 0 and node != None: 
			node = node.next
			pos -= 1
		return node
	def showList(self):
		node = self.head
		while node :
			print(node.data, end=' ')
			node = node.next

myList = SinglyLinkedList()
myList.func1(1); myList.func2(2)
myList.func1(3); myList.func2(4)
myList.func2(myList.func3(0).data)
myList.showList()