[Python] 纯文本查看 复制代码
class Node(object):
"""节点类"""
def __init__(self, item):
self.item = item
self.lChild = None
self.rChild = None
class Tree(object):
"""二叉树"""
def __init__(self):
#记录根节点
self.root = None
def add(self, item):
# 添加节点
# 完全二叉树，从上到下，从左往右
node = Node(item)
if self.root is None:
self.root = node
else:
# 从上到下，从左往右 使用队列
queue = []
queue.append(self.root)
while queue:
child = queue.pop(0)
if child.lChild is None:
child.lChild = node
return
if child.rChild is None:
child.rChild = node
return
queue.append(child.lChild)
queue.append(child.rChild)
# 广度优先遍历，层次遍历
def breath_travel(self):
if self.root is None:
return
queue = []
queue.append(self.root)
while queue:
node = queue.pop(0)
print(node.item, end=" ")
if node.lChild is not None:
queue.append(node.lChild)
if node.rChild is not None:
queue.append(node.rChild)
# 深度优先遍历
def depth_travel(self):
self.post_order(self.root)
print()
# 先序 自己 左子树 右子树
def pre_order(self, node):
if node is None:
return
print(node.item, end=" ")
self.pre_order(node.lChild)
self.pre_order(node.rChild)
# 中序 左子树 自己 右子树
def in_order(self, node):
if node is None:
return
self.in_order(node.lChild)
print(node.item, end=" ")
self.in_order(node.rChild)
# 后序 左子树 右子树 自己
def post_order(self, node):
if node is None:
return
self.post_order(node.lChild)
self.post_order(node.rChild)
print(node.item, end=" ")
if __name__ == '__main__':
tree = Tree()
tree.add(0)
tree.add(1)
tree.add(2)
tree.add(3)
tree.add(4)
tree.add(5)
tree.add(6)
tree.add(7)
tree.add(8)
tree.add(9)
# tree.breath_travel()
tree.depth_travel()