python 实现二叉树

转自    https://blog.csdn.net/weixin_42521211/article/details/88956908

class Tree(object):
    def __init__(self, value):
        self.data = value
        self.left = None
        self.right = None

    def insertLeft(self, value_left):
        self.left = Tree(value_left)
        return self.left

    def insertRight(self, value_right):
        self.right = Tree(value_right)
        return self.right


    def show(self):
        print(self.data)

# 先序
def preOrder(node):
    if node.data:
        node.show()
        if node.left:
            preOrder(node.left)
        if node.right:
            preOrder(node.right)

# 中序
def midOrder(node):
    if node.data:
        if node.left:
            midOrder(node.left)
        node.show()
        if node.right:
            midOrder(node.right)

# 后序
def botOrder(node):
    if node.data:
        if node.left:
            botOrder(node.left)
        if node.right:
            botOrder(node.right)
        node.show()

if __name__ == '__main__':

    root = Tree("root")

    A = root.insertLeft('A')
    B = root.insertRight('B')
    C = A.insertLeft('C')
    D = A.insertRight('D')
    F = D.insertLeft('F')
    G = D.insertRight('G')

    E =B.insertRight('E')
    # preOrder(root)
    # midOrder(root)
    botOrder(root)