# coding:utf8
#节点类
class Node():
def __init__(self, _item):
self.item = _item
self.next = None
#链表类
class Link():
def __init__(self):
self._head = None
def add(self, _item):
node = Node(_item)
node.next = self._head
self._head = node
def append(self, _item):
node = Node(_item)
cur = self._head
pre = None
# 链表为空，追加的为第一个节点时
if cur == None:
self._head = node
return
while cur:
pre = cur
cur = cur.next
pre.next = node
def insert(self, pos, _item):
node = Node(_item)
pre = None
cur = self._head
for i in range(pos):
pre = cur
cur = cur.next
pre.next = node
node.next = cur
def remove(self, _item):
pre = None
cur = self._head
# 如果删除项为首部节点
if cur.item == _item:
self._head = cur.next
return
while cur:
pre = cur
cur = cur.next
if cur == None:
return
if cur.item == _item:
pre.next = cur.next
return
def search(self, _item):
flag = False
cur = self._head
while cur:
if cur.item == _item:
flag = True
cur = cur.next
return flag
def travel(self):
cur = self._head
while cur:
print(cur.item)
cur = cur.next
def isEmpty(self):
return self._head == Node
def size(self):
cur = self._head
count = 0
while cur:
count += 1
cur = cur.next
return count
if __name__ == "__main__":
link = Link()
link.add(1)
link.add(2)
link.add(3)
link.append(4)
link.append(5)
link.insert(1, 7)
link.travel()
link.remove(5)
link.travel()
print(link.isEmpty())
print(link.size())
print(link.search(5))
print(link.search(6))