from collections import deque


class Solution():

    def reverseList(self, head):

        if not head:
            return None
        deq = deque()

        while head.next:
            deq.append(head)
            head = head.next

        tmp = head

        while deq:
            node = deq.pop()
            node.next = tmp.next
            tmp.next = node
            tmp = node
        return head