def insert(self, data, pos=0):
if pos <= 0:
self.add(data)
elif pos > self.size() - 1:
self.append(data)
else:
newNode = Node(data)
preHead = self.__head
count = 0
# preHead指向指定位置前一个位置pos-1
while count < pos - 1:
count += 1
preHead = preHead.getNext()
# 新节点的指针域指向插入位置的节点
newNode.setNext(preHead.getNext())
# 插入位置前一个节点的指针域指向新节点
preHead.setNext(newNode)
def append(self, data):
newNode = Node(data)
if self.isEmpty():
self.__head = newNode
else:
currentHead = self.__head
while currentHead.getNext() is not None:
currentHead = currentHead.getNext()
currentHead.setNext(newNode)
def add(self, data):
newNode = Node(data)
if self.isEmpty():
self.__head = newNode
newNode.setNext(self.__head)
else:
# 创建新节点，其指针域指向头节点
newNode = Node(data, nextp=self.__head)
currentHead = self.__head
while currentHead.getNext() is not self.__head:
currentHead = currentHead.getNext()
# 尾节点指向新节点
currentHead.setNext(newNode)
self.__head = newNode
# preOrder = N L R
# inOrder = L K R
# postOrder = L R N
def size(root):
if root is None:
return 0
i = size(root.left)
j = size(root.right)
sum = i + j + 1
return sum
root = Node(1)
root.left = Node(2)
root.right = Node(3)
root.right.left = Node(6)
root.right.right = Node(7)
root.left.left = Node(4)
root.left.right = Node(5)
print(size(root))
def push(self, data):
newNode = Node(data, nextp=self.__head)
self.__head = newNode
self.__count += 1
def add(self, data):
# 创建新节点，其指针域指向头节点
newNode = Node(data, nextp=self.__head)
# 头节点指向新节点
self.__head = newNode