单链表反转

def solve():
    class Node:
        def __init__(____):
            self.data = data
            self.next = None
    head = None
    for val in [____, ____, ____, ____, ____]:
        new_node = Node(____)
        if head is None:
            head = new_node
        else:
            cur = head
            while cur.next:
                cur = cur.next
            cur.next = new_node
    prev = None
    cur = head
    while cur:
        nxt = cur.next
        cur.next = prev
        prev = cur
        cur = nxt
    head = prev
    cur = head
    while cur:
        print(____)
        cur = cur.next