[AppleScript] 纯文本查看 复制代码
class Node(object): """双向链表节点""" def __init__(self, item): self.item = item self.next = None self.prev = None
class DLinkList(object): """双向链表""" def __init__(self): self.__head = None
def is_empty(self): """判断链表是否为空""" return self.__head == None
def length(self): """返回链表的⻓度""" cur = self.__head count = 0 while cur != None: count += 1 cur = cur.next return count
def travel(self): """遍历链表""" cur = self.__head while cur != None: print cur.item, cur = cur.next print ""
def add(self, item): """头部插⼊元素""" node = Node(item) if self.is_empty(): # 如果是空链表，将_head指向node self.__head = node else: # 将node的next指向_head的头节点 node.next = self.__head # 将_head的头节点的prev指向node
self.__head.prev = node # 将_head 指向node self.__head = node
def append(self, item): """尾部插⼊元素""" node = Node(item) if self.is_empty(): # 如果是空链表，将_head指向node self.__head = node else: # 移动到链表尾部 cur = self.__head while cur.next != None: cur = cur.next # 将尾节点cur的next指向node cur.next = node # 将node的prev指向cur node.prev = cur
def search(self, item): """查找元素是否存在""" cur = self.__head while cur != None: if cur.item == item: return True cur = cur.next return False
