# -*- coding:utf-8 -*-
# 日期：2018/6/12 8:37
# Author:小鼠标

# 节点对象
class Node:
  def __init__(self):
    self.left_children = None
    self.left_height = 0
    self.right_children = None
    self.right_height = 0
    self.value = None

# 二叉树对象
class tree:
  def __init__(self):
    self.root = False
    self.front_list = []
    self.middle_list = []
    self.after_list = []
  # 生成二叉树
  def create_tree(self,n=0,l=[]):
    if l == []:
      print("传入的列表为空")
      return
    if n > len(l)-1:
      print("二叉树生成")
      return
    node = Node()
    node.value = l[n]
    if not self.root:
      self.root = node
      self.list = l
    else:
      self.add(self.root,node)
    self.create_tree(n+1,l)
  # 添加节点
  def add(self,parent,new_node):
    if new_node.value > parent.value:
      # 插入值比父亲值大，所以在父节点右边
      if parent.right_children == None:
        parent.right_children = new_node
        # 新插入节点的父亲节点的高度值为1，也就是子高度值0+1
        parent.right_height = 1
        # 插入值后 从下到上更新节点的height
      else:
        self.add(parent.right_children,new_node)
        # 父亲节点的右高度等于右孩子，左右高度中较大的值 + 1
        parent.right_height = max(parent.right_children.right_height, parent.right_children.left_height) + 1
        # ======= 此处开始判断平衡二叉树=======
        # 右边高度大于左边高度 属于右偏
        if parent.right_height - parent.left_height >= 2:
          self.right_avertence(parent)
    else:
      # 插入值比父亲值小，所以在父节点左边
      if parent.left_children == None:
        parent.left_children = new_node
        parent.left_height = 1
      else:
        self.add(parent.left_children,new_node)
        parent.left_height = max(parent.left_children.right_height, parent.left_children.left_height) + 1
        # ======= 此处开始判断平衡二叉树=======
        # 左边高度大于右边高度 属于左偏
        if parent.left_height - parent.right_height >= 2:
          self.left_avertence(parent)
  # 更新当前节点下的所有节点的高度
  def update_height(self,node):
    # 初始化节点高度值为0
    node.left_height = 0
    node.right_height = 0
    # 是否到最底层的一个
    if node.left_children == None and node.right_children == None:
      return
    else:
      if node.left_children:
        self.update_height(node.left_children)
        # 当前节点的高度等于左右子节点高度的较大值 + 1
        node.left_height = max(node.left_children.left_height,node.left_children.right_height) + 1
      if node.right_children:
        self.update_height(node.right_children)
        # 当前节点的高度等于左右子节点高度的较大值 + 1
        node.right_height = max(node.right_children.left_height, node.right_children.right_height) + 1
      # 检查是否仍有不平衡
      if node.left_height - node.right_height >= 2:
        self.left_avertence(node)
      elif node.left_height - node.right_height <= -2:
        self.right_avertence(node)

  def right_avertence(self,node):
    # 右偏 就将当前节点的最左节点做父亲
    new_code = Node()
    new_code.value = node.value
    new_code.left_children = node.left_children
    best_left = self.best_left_right(node.right_children)
    v = node.value
    # 返回的对象本身,
    if best_left == node.right_children and best_left.left_children == None:
      # 说明当前节点没有有节点
      node.value = best_left.value
      node.right_children = best_left.right_children
    else:
      node.value = best_left.left_children.value
      best_left.left_children = best_left.left_children.right_children
    node.left_children = new_code
    self.update_height(node)

  # 处理左偏情况
  def left_avertence(self,node):
    new_code = Node()
    new_code.value = node.value
    new_code.right_children = node.right_children
    best_right = self.best_left_right(node.left_children,1)
    v = node.value
    # 返回的对象本身,
    if best_right == node.left_children and best_right.right_children == None:
      # 说明当前节点没有有节点
      node.value = best_right.value
      node.left_children = best_right.left_children
    else:
      node.value = best_right.right_children.value
      best_right.right_children = best_right.right_children.left_children
    node.right_children = new_code
    self.update_height(node)
  # 返回node节点最左（右）子孙的父级
  def best_left_right(self,node,type=0):
    # type=0 默认找最左子孙
    if type == 0:
      if node.left_children == None:
        return node
      elif node.left_children.left_children == None:
        return node
      else:
        return self.best_left_right(node.left_children,type)
    else:
      if node.right_children == None:
        return node
      elif node.right_children.right_children == None:
        return node
      else:
        return self.best_left_right(node.right_children,type)
  # 前序(先中再左最后右)
  def front(self,node=None):
    if node == None:
      self.front_list = []
      node = self.root
    # 输出当前节点
    self.front_list.append(node.value)
    # 先判断左枝
    if not node.left_children == None:
      self.front(node.left_children)
    # 再判断右枝
    if not node.right_children == None:
      self.front(node.right_children)
    # 返回最终结果
    return self.front_list
  # 中序(先左再中最后右)
  def middle(self,node=None):
    if node == None:
      node = self.root
    # 先判断左枝
    if not node.left_children == None:
      self.middle(node.left_children)
    # 输出当前节点
    self.middle_list.append(node.value)
    # 再判断右枝
    if not node.right_children == None:
      self.middle(node.right_children)
    return self.middle_list
  # 后序(先左再右最后中)
  def after(self,node=None):
    if node == None:
      node = self.root
    # 先判断左枝
    if not node.left_children == None:
      self.after(node.left_children)
    # 再判断右枝
    if not node.right_children == None:
      self.after(node.right_children)
    self.after_list.append(node.value)
    return self.after_list
  # 节点删除
  def del_node(self,v,node=None):
    if node == None:
      node = self.root
      # 删除根节点
      if node.value == v:
        self.del_root(self.root)
        return
    # 删除当前节点的左节点
    if node.left_children:
      if node.left_children.value == v:
        self.del_left(node)
        return
    # 删除当前节点的右节点
    if node.right_children:
      if node.right_children.value == v:
        self.del_right(node)
        return
    if v > node.value:
      if node.right_children:
        self.del_node(v, node.right_children)
      else:
        print("删除的元素不存在")
    else:
      if node.left_children:
        self.del_node(v, node.left_children)
      else:
        print("删除的元素不存在")
  #删除当前节点的右节点
  def del_right(self,node):
    # 情况1 删除节点没有右枝
    if node.right_children.right_children == None:
      node.right_children = node.right_children.left_children
    else:
      best_left = self.best_left_right(node.right_children.right_children)
      # 表示右枝最左孙就是右枝本身
      if best_left == node.right_children.right_children and best_left.left_children == None:
        node.right_children.value = best_left.value
        node.right_children.right_children = best_left.right_children
      else:
        node.right_children.value = best_left.left_children.value
        best_left.left_children = best_left.left_children.right_children
  # 删除当前节点的左节点
  def del_left(self,node):
    # 情况1 删除节点没有右枝
    if node.left_children.right_children == None:
      node.left_children = node.left_children.left_children
    else:
      best_left = self.best_left_right(node.left_children.right_children)
      # 表示右枝最左子孙就是右枝本身
      if best_left == node.left_children.right_children and best_left.left_children == None:
        node.left_children.value = best_left.value
        node.left_children.right_children = best_left.right_children
      else:
        node.left_children.value = best_left.left_children.value
        best_left.left_children = best_left.left_children.right_children
  # 删除根节点
  def del_root(self,node):
    if node.right_children == None:
      if node.left_children == None:
        node.value = None
      else:
        self.root = node.left_children
    else:
      best_left = self.best_left_right(node.right_children)
      # 表示右枝最左子孙就是右枝本身
      if best_left == node.right_children and best_left.left_children == None:
        node.value = best_left.value
        node.right_children = best_left.right_children
      else:
        node.value = best_left.left_children.value
        best_left.left_children = best_left.left_children.right_children

  # 搜索
  def search(self,v,node=None):
    if node == None:
      node = self.root
    if node.value == v:
      return True
    if v > node.value:
      if not node.right_children == None:
        return self.search(v, node.right_children)
    else:
      if not node.left_children == None:
        return self.search(v, node.left_children)
    return False
if __name__ == '__main__':
  # 需要建立二叉树的列表
  list = [4, 6, 3, 1, 7, 9, 8, 5, 2]
  t = tree()
  t.create_tree(0,list)
  res = t.front()
  print('前序', res)