#encoding=utf-8class Tree():  def __init__(self,leftjd=0,rightjd=0,data=0):    self.leftjd = leftjd  　　self.rightjd = rightjd  　　self.data = data class Btree():  def __init__(self,base=0):  　　self.base = base  #前序遍歷 根左右  def qout(self,jd):    if jd == 0:    return  print jd.data  self.qout(jd.leftjd)  self.qout(jd.rightjd)  #中序遍歷 左根右  def mout(self,jd):  if jd == 0:    return  self.mout(jd.leftjd)  print jd.data  self.mout(jd.rightjd)  #后序遍歷 左右根  def hout(self,jd):  if jd == 0:    return  self.hout(jd.leftjd)  self.hout(jd.rightjd)  print jd.datajd1 = Tree(data=8)jd2 = Tree(data=9)base = Tree(jd1,jd2,7)x = Btree(base)x.qout(x.base)print '/r/n'x.mout(x.base)print '/r/n'x.hout(x.base)