java三叉树算法

‘壹’ 求一个python的三叉树算法

这是网络上的一个版本，我自己做了一点修改，这是一个n叉树，希望对你有所帮助

#!/usr/bin/python
#-*-coding:utf-8-*-
'''
Createdon2014-3-26

@author:qcq
'''

#==============================================================================
#tree.py:
#==============================================================================
#--
#$Revision:1.7$
#$Date:2000/03/2922:36:12$
#modifiedbyqcqin2014/3/27
#modifiedbyqcqin2014/4/23增加了遍历树的非递归版本的广度优先和深度优先
#--

#================================================================
#Contents
#----------------------------------------------------------------
#classTree:Genericn-arytreenodeobject
#classNodeId:Representsthepathtoanodeinann-arytree
#----------------------------------------------------------------

#importstring


classTree:
"""Genericn-arytreenodeobject

Childrenareadditive;noprovisionfordeletingthem.
:0forthefirst
childadded,1forthesecond,andsoon.

modifiedbyqcqin2014/3/27.

Exports:
Tree(parent,value=None)Constructor
.parentIfthisistherootnode,None,otherwise
theparent'sTreeobject.
.childListListofchildren,zeroormoreTreeobjects.
.valueValuepassedtoconstructor;canbeanytype.
.birthOrderIfthisistherootnode,0,otherwisethe
indexofthischildintheparent's.childList
.nChildren()Returnsthenumberofself'schildren.
.nthChild(n)Returnsthenthchild;raisesIndexErrorif
nisnotavalidchildnumber.
.fullPath():.
.nodeId():ReturnspathtoselfasaNodeId.
"""


#---Tree.__init__---

def__init__(self,parent,value=None):
"""ConstructorforaTreeobject.

[if(parentisNoneoraTreeobject)->
if(parentisNone)->
,nochildren,
andvalue(value)
else->

ofparent(parent)andnochildren,andvalue(value)
]
"""
#--1--
self.parent=parent
self.value=value
self.childList=[]

#--2--
#-[if(parentisNone)->
#self.birthOrder:=0
#else->
#parent:=
#self.birthOrder:=sizeofparent's.childList
#-]
ifparentisNone:
self.birthOrder=0
else:
self.birthOrder=len(parent.childList)
parent.childList.append(self)


#---Tree.nChildren---

defnChildren(self):
"""[
]
"""
returnlen(self.childList)


#---Tree.nthChild---

defnthChild(self,n):
"""[if(nisaninteger)->
if(0<=n<(numberofself'schildren)->
returnself's(n)thchild,countingfrom0
else->
raiseIndexError
]
"""
returnself.childList[n]


#---Tree.fullPath---

deffullPath(self):
""".

[returnasequence[c0,c1,...,ci]suchthatselfis
root.nthChild(c0).nthChild(c1).....nthChild(ci),or
anemptylistifselfistheroot]
"""

#--1--
result=[]
parent=self.parent
kid=self

#--2--
#[result+:=childnumbersfromparenttoroot,in
#reverseorder]
whileparent:
result.insert(0,kid.birthOrder)
parent,kid=parent.parent,parent

#--3--
returnresult


#---Tree.nodeId---

defnodeId(self):
""".
"""
#--1--
#[fullPath:=sequence[c0,c1,...,ci]suchthatselfis
#root.nthChild(c0).nthChild(c1).....nthChild(ci),or
#anemptylistifselfistheroot]
fullPath=self.fullPath()

#--2--
returnNodeId(fullPath)

defequals(self,node):
'''
'''
returnself.value==node.value

#===========================================================================
#deletethenodefromthetree
#===========================================================================
defdelete(self):
ifself.parentisNone:
return
else:
#temp=self.birthOrder
'''
ifdeletethemiddletreeobject,
.
'''
self.parent.childList.remove(self.parent.childList[self.birthOrder])
fori,jinzip(range(self.birthOrder+1,self.parent.nChildren()),self.parent.childList[self.birthOrder+1:]):
j.birthOrder=j.birthOrder-1


defupdate(self,value):
'''

'''
self.value=value

def__str__(self):
return"The%dchildwithvalue%d"%(self.birthOrder,self.value)#-----classNodeId-----

classNodeId:
""".

Exports:
NodeId(path):
[->
-id]
.path:[aspassedtoconstructor]
.__str__():[returnselfasastring]
.find(root):
[ifrootisaTreeobject->

treerootedat(root)->
returnthe.valueofthatnode
else->
returnNone]
.isOnPath(node):
[ifnodeisaTreeobject->
->
return1
else->
return0]
"""

#---NodeId.__init__---

def__init__(self,path):
"""ConstructorfortheNodeIdobject
"""
self.path=path


#---NodeId.__str__---

def__str__(self):
"""Returnselfindisplayableform
"""

#--1--
#[L:=alistoftheelementsofself.pathconvertedtostrings]
L=map(str,self.path)

#--2--
#["/"]
returnstring.join(L,"/")


#---NodeId.find---

deffind(self,node):
"""
"""
returnself.__reFind(node,0)


#---NodeId.__reFind---

def__reFind(self,node,i):
"""Recursivenodefindingroutine.Startsatself.path[i:].

[if(nodeisaTreeobject)
and(0<=i<=len(self.path))->
ifi==len(self.path)->
returnnode'svalue
elseifself.path[i:]describesapathfromnode
tosometreeobjectT->
returnT
else->
returnNone]
"""

#--1--
ifi>=len(self.path):
returnnode.value#We'rethere!
else:
childNo=self.path[i]

#--2--
#[->
#child:=thatchildnode
#else->
#returnNone]
try:
child=node.nthChild(childNo)
exceptIndexError:
returnNone

#--3--
#[if(i+1)==len(self.path)->
#returnchild
#elseifself.path[i+1:]describesapathfromnodeto
#sometreeobjectT->
#returnT
#else->
#returnNone]
returnself.__reFind(child,i+1)


#---NodeId.isOnPath---

defisOnPath(self,node):
"""Isself'spathtoorthroughthegivennode?
"""

#--1--
#[nodePath:=pathlistfornode]
nodePath=node.fullPath()

#--2--
#[ifnodePathisaprefixof,oridenticaltoself.path->
#return1
#else->
#return0]
iflen(nodePath)>len(self.path):
return0#Nodeisdeeperthanself.path

foriinrange(len(nodePath)):
ifnodePath[i]!=self.path[i]:
return0#Nodeisadifferentroutethanself.path

return1

‘贰’ 我的世界怎么设置一个人的重生点

命令方块
首先输入/give @p command_block 获得一个命令方块
然后放在地上，输入/spawnpoint @p
旁边放一个压力板，就可以了。