Python實現 鏈表的逆序

鏈表逆序

def func(head):
    if head == None or head.next == None: #邊界條件
        return head
    p1 = head #循環變量1
    p2 = head.next #循環變量2
    tmp = None #保存數據的臨時變量
    while p2:
        tmp = p2.next
        p2.next = p1
        p1 = p2
        p2 = tmp
    head.next = None
    return p1