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

class LinkedList:
  def __init__(self):
    self.head = None

  # print list of linked list
  def print_list(self):
    cur_node = self.head
    while cur_node:
      print(cur_node.data)
      cur_node = cur_node.next

  # add to end of linked list
  def append(self, data):
    new_node = Node(data)
    cur = self.head

    if self.head is None:
      self.head = new_node
      return

    while cur.next:
      cur = cur.next
    cur.next = new_node

  def prepend(self, data):
    new_node = Node(data)
    new_node.next = self.head
    self.head = new_node

  def reverse_iterative(self):

    prev = None
    cur = self.head
    while cur:
        nxt = cur.next
        cur.next = prev

        prev = cur
        cur = nxt
    self.head = prev


ll = LinkedList()
ll.append("A")
ll.append("B")
ll.append("C")
ll.append("D")
ll.prepend("E")
print("given")
ll.print_list()
print("reversed list")
ll.reverse_iterative()
ll.print_list()