[硕.Love Python] BinarySearchTree(二叉搜索树)

class  Node( object ):
    __slots__  =  [ 'left' ,  'right' ,  'data' ]

    def  __init__( self , data, left = None , right = None ):
        self .data  =  data
        self .left  =  left
        self .right  =  right

    def  __str__( self ):
        sl  =  '%s <-'  %  self .left  if  self .left  else  ''
        sr  =  '-> %s'  %  self .right  if  self .right  else  ''
        return  '[%s Node(%s) %s]'  %  (sl,  self .data, sr)

class  BinarySearchTree( object ):
    def  __init__( self ):
        self .root  =  None

    def  insert( self , data):
        node, parent  =  self .search(data,  True )
        if  node:
            raise  ValueError( '"%s" has been in tree.'  %  data)

        node  =  Node(data)
        if  parent  is  None :
            self .root  =  node
        elif  data < parent.data:
            parent.left  =  node
        else :
            parent.right  =  node

    def  search( self , data, retParent = False ):
        parent  =  None
        node  =  self .root

        while  node  and  node.data ! =  data:
            parent  =  node
            if  data < node.data:
                node  =  node.left
            else :
                node  =  node.right

        return  (node, parent)  if  retParent  else  node

    def  delete( self , data):
        self ._deleteNode( * self .search(data,  True ))

    def  _findBiggest( self , node):
        parent  =  None
        while  node.right:
            parent  =  node
            node  =  node.right
        return  node, parent

    def  _deleteNode( self , node, parent):
        if  node  is  None :
            return

        if  node.left  and  node.right:
            tmp, tmpParent  =  self ._findBiggest(node.left)
            if  tmpParent  is  not  None :
                tmpParent.right  =  tmp.left
                tmp.left  =  node.left
            tmp.right  =  node.right
        else :
            tmp  =  node.left  or  node.right

        if  parent  is  None :
            self .root  =  tmp
        elif  parent.left  is  node:
            parent.left  =  tmp
        else :
            parent.right  =  tmp

if  __name__  = =  '__main__' :
    bst  =  BinarySearchTree()
    while  True :
        cmd  =  ( raw_input ( '$ ' )).strip().split()
        if  cmd[ 0 ]  = =  'i' :
            bst.insert( int (cmd[ 1 ]))
            print  bst.root
        elif  cmd[ 0 ]  = =  'd' :
            bst.delete( int (cmd[ 1 ]))
            print  bst.root

刘硕老师Python精品课程：

《Python高级编程技巧实战》：

http://coding.imooc.com/class/62.html

 

《Python算法实战视频课程》：

http://edu.csdn.net/combo/detail/174

 

《Python科学计算—NumPy实战课程》：

http://edu.51cto.com/course/course_id-5046.html

 

熊猫TV直播间：

http://www.panda.tv/671023