线索二叉树

节点类。

因为不会使用java的enum。所以RTag和LTag就使用String凑活用吧。

 

package struct;



public class BiThrNode {

    private String data;

    private BiThrNode lchild;

    private BiThrNode rchild;

    private String LTag;   //Thread或null

    private String RTag;

    public String getData() {

        return data;

    }

    public void setData(String data) {

        this.data = data;

    }

    public BiThrNode getLchild() {

        return lchild;

    }

    public void setLchild(BiThrNode lchild) {

        this.lchild = lchild;

    }

    public BiThrNode getRchild() {

        return rchild;

    }

    public void setRchild(BiThrNode rchild) {

        this.rchild = rchild;

    }

    public String getLTag() {

        return LTag;

    }

    public void setLTag(String lTag) {

        LTag = lTag;

    }

    public String getRTag() {

        return RTag;

    }

    public void setRTag(String rTag) {

        RTag = rTag;

    }

    

}

 

二叉树线索化及中序遍历的方法。

以及演示代码：

package demo;



import struct.BiThrNode;



public class BiThrTree {

    //pre为全局变量

    public static BiThrNode pre;

    //中序遍历线索化

    public static void InThreading(BiThrNode p){

        if(p!=null){

            InThreading(p.getLchild());

            if(p.getLchild()==null){

                p.setLTag("Thread");

                p.setLchild(pre);

            }

            if(pre.getRchild()==null){

                pre.setRTag("Thread");

                pre.setRchild(p);

            }

            pre=p;

            InThreading(p.getRchild());

        }

    }

    

    public static void InOrderTraverse_Thr(BiThrNode T){

        BiThrNode p;

        p = T.getLchild();   //p指向根节点

        while(p != T){

            while(p.getLTag() == null){

                p = p.getLchild();

            }

            System.out.print(p.getData() + " ");

            while(p.getRTag()=="Thread"){

                p = p.getRchild();

                System.out.println(p.getData() + " ");

            }

            p = p.getRchild();

        }

    }

    public static void main(String[] args){

        BiThrNode ba = new BiThrNode();

        BiThrNode bb = new BiThrNode();

        BiThrNode bc = new BiThrNode();

        BiThrNode bd = new BiThrNode();

        BiThrNode be = new BiThrNode();

        BiThrNode bf = new BiThrNode();

        BiThrNode head = new BiThrNode();

        ba.setLchild(bb);

        ba.setRchild(bc);

        bb.setLchild(bd);

        bb.setRchild(be);

        bc.setRchild(bf);

        head.setLchild(ba);

        ba.setData("A");

        bb.setData("B");

        bc.setData("C");

        bd.setData("D");

        be.setData("E");

        bf.setData("F");

        BiThrNode p = ba;

        pre = p;

        InThreading(p);

          p = head;

        InOrderTraverse_Thr(p);

    }

}