二叉树 BinaryTree （先序、中序、后序遍历节点查找、插入、删除完整类） Java数据结构与算法

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/** 
 * 
 * @author sunnyykn 
 */  
import java.io.*;  
import java.util.*;  
class Node  
{  
    public int iData;       //data item (key)  
    public double dData;    //data item  
    public Node leftChild;  //this node's left child  
    public Node rightChild; //this node's right child  
    public void displayNode()   //display ourself  
    {  
        System.out.print("{");  
        System.out.print(iData);  
        System.out.print(",");  
        System.out.print(dData);  
        System.out.print("}");  
    }  
}//end class Node  
class Tree  
{  
    private Node root;      //first node of tree  
    public Tree()  
    {  
        root = null;        //no nodes in tree yet  
    }  
    public Node find(int key)   //find node with given key  
    {  
        Node current = root;        //start at root  
        while(current.iData != key) //while no match  
        {  
            if(key < current.iData) //go left?  
                current = current.leftChild;  
            else                    //go right?  
                current = current.rightChild;  
            if (current == null)    //didn't find it  
                return null;  
        }  
        return current;  
    }//end find()  
    public void insert(int id ,double dd)  
    {  
        Node newNode = new Node();      //make new node  
        newNode.iData = id;             //insert data  
        newNode.dData = dd;  
        if( root == null )              //no node in root  
            root = newNode;  
        else  
        {  
            Node current = root;        //start at root  
            Node parent;  
            while( true )  
            {  
                parent = current;  
                if(id < current.iData)  //go left?  
                {  
                    current = current.leftChild;  
                    if(current == null)  //if end of the line  
                    {  
                        parent.leftChild = newNode;  
                        return ;  
                    }  
                }//end if go left  
                else                    //or go right  
                {  
                    current = current.rightChild;  
                    if(current == null) //if end of the line  
                    {  
                        parent.rightChild = newNode;  
                        return ;  
                    }  
                }//end else go right  
            }//end while  
        }//end else not root  
    }//end insert()  
    public boolean delete(int key)      //delete node with given key  
    {  
        Node current = root;  
        Node parent = root;  
        boolean isLeftChild = true;  
        while(current.iData != key)  
        {  
            parent = current;  
            if(key < current.iData)  
            {  
                isLeftChild = true;  
                current = current.leftChild;  
            }  
            else  
            {  
                isLeftChild = false;  
                current = current.rightChild;  
            }  
            if(current == null)  
                return false;  
        }//end while  
        //found node to delete  
        //if no children , simply delete it  
        if(current.leftChild == null && current.rightChild == null)  
        {  
            if (current == root)  
                root = null;  
            else if(isLeftChild)  
                parent.leftChild = null;  
            else  
                parent.rightChild = null;  
        }  
        //if no right child , replace with left subtree  
        else if(current.rightChild == null)  
        {  
            if (current == root)  
                root = current.leftChild;  
            else if (isLeftChild)  
                parent.leftChild = current.leftChild;  
            else  
                parent.rightChild = current.leftChild;  
        }  
        //if no left child , replace with right subtree  
        else if (current.leftChild == null)  
        {  
            if (current == root)  
                root = current.rightChild;  
            else if(isLeftChild)  
                parent.leftChild = current.rightChild;  
            else  
                parent.rightChild = current.rightChild;  
        }  
        //two children,so replace with inorder successor  
        else  
        {  
            //get successor of node to delete(current)  
            Node successor = getSuccessor(current);  
            //connect parent of current to successor insteed  
            if(current == root)  
                root = successor;  
            else if (isLeftChild)  
                parent.leftChild = successor;  
            else   
                parent.rightChild = successor;  
            //connect successor to current's left child  
            successor.leftChild = current.leftChild;  
        }//end else two children  
        //(successor cannot have a left child)  
        return true;  
    }//end delete()  
    //return node with next-highest value after delNode  
    //goes to right child , then right child's left descendents  
    private Node getSuccessor(Node delNode)  
    {  
        Node successorParent = delNode;  
        Node successor = delNode;  
        Node current = delNode.rightChild;      //go to right child  
        while(current != null)                  //until no more left children  
        {  
            successorParent = successor;  
            successor = current;  
            current = current.leftChild;        //go to left child  
        }  
        if (successor != delNode.rightChild)    //if successor not right child , make connections  
        {  
            successorParent.leftChild = successor.rightChild;  
            successor.rightChild = delNode.rightChild;  
        }  
        return successor;  
    }  
    public void traverse(int traverseType)  
    {  
        switch(traverseType)  
        {  
            case 1:  
                System.out.print("/nPreorder traversal:");  
                preOrder(root);  
                break;  
            case 2:  
                System.out.print("/nInorder traversal: ");  
                inOrder(root);  
                break;  
            case 3:  
                System.out.print("/nPostorder traversal:");  
                postOrder(root);  
                break;  
        }  
        System.out.println("");  
    }  
    private void preOrder(Node localRoot)  
    {  
        if (localRoot != null)  
        {  
            System.out.print(localRoot.iData + " ");  
            preOrder(localRoot.leftChild);  
            preOrder(localRoot.rightChild);  
        }  
    }  
    private void inOrder(Node localRoot)  
    {  
        if(localRoot != null)  
        {  
            inOrder(localRoot.leftChild);  
            System.out.print(localRoot.iData + " ");  
            inOrder(localRoot.rightChild);  
        }  
    }  
    private void postOrder(Node localRoot)  
    {  
        if (localRoot != null)  
        {  
            postOrder(localRoot.leftChild);  
            postOrder(localRoot.rightChild);  
            System.out.print(localRoot.iData + " ");  
        }  
    }  
    public void displayTree()  
    {  
        Stack globalStack = new Stack();  
        globalStack.push(root);  
        int nBlanks = 32;  
        boolean isRowEmpty = false ;  
        System.out.println("....................................................");  
        while(isRowEmpty == false)  
        {  
            Stack localStack = new Stack();  
            isRowEmpty = true;  
            for(int j = 0;j < nBlanks; j ++)  
                System.out.print(" ");  
            while(globalStack.isEmpty() == false)  
            {  
                Node temp = (Node)globalStack.pop();  
                if(temp != null)  
                {  
                    System.out.print(temp.iData);  
                    localStack.push(temp.leftChild);  
                    localStack.push(temp.rightChild);  
                    if(temp.leftChild != null || temp.rightChild != null)  
                        isRowEmpty = false;  
                }  
                else  
                {  
                    System.out.print("--");  
                    localStack.push(null);  
                    localStack.push(null);  
                }  
                for(int j = 0; j < nBlanks*2 - 2;j ++)  
                    System.out.print(" ");  
            }//end while globalStack not empty  
            System.out.println("");  
            nBlanks /= 2;  
            while(localStack.isEmpty() == false)  
                globalStack.push( localStack.pop() );  
        }//end while isRowEmpty is false  
        System.out.println("....................................................");  
    }//end displayTree()  
}//end class Tree  
class TreeApp  
{  
    public static void main(String[] args) throws IOException  
    {  
        int value ;  
        Tree theTree = new Tree();  
          
        theTree.insert(50, 1.5);  
        theTree.insert(25, 1.2);  
        theTree.insert(75, 1.7);  
        theTree.insert(12, 1.5);  
        theTree.insert(37, 1.2);  
        theTree.insert(43, 1.7);  
        theTree.insert(30, 1.5);  
        theTree.insert(33, 1.2);  
        theTree.insert(87, 1.7);  
        theTree.insert(93, 1.5);  
        theTree.insert(97, 1.5);  
        while( true )  
        {  
            System.out.print("Enter first letter of show,insert,find,delete,or traverse:");  
            int choice = getChar();  
            switch( choice )  
            {  
                case 's':  
                    theTree.displayTree();  
                    break;  
                case 'i':  
                    System.out.print("Enter value to insert:");  
                    value = getInt();  
                    theTree.insert(value, value + 0.9);  
                    break;  
                case 'f':  
                    System.out.print("Enter value to find:");  
                    value = getInt();  
                    Node found = theTree.find(value);  
                    if(found != null)  
                    {  
                        System.out.print("Found:");  
                        found.displayNode();  
                        System.out.print("/n");  
                    }  
                    else  
                    {  
                        System.out.print("Could not find ");  
                        System.out.print(value + '/n');  
                    }  
                    break;  
                case 'd':  
                    System.out.print("Enter value to delete:");  
                    value = getInt();  
                    boolean didDelete = theTree.delete(value);  
                    if(didDelete)  
                        System.out.print("Deleted " + value + '/n');  
                    else{  
                        System.out.print("Could not delete ");  
                        System.out.print(value + '/n');  
                    }  
                    break;  
                case 't':  
                    System.out.print("Enter type 1,2 or 3:");  
                    value = getInt();  
                    theTree.traverse(value);  
                    break;  
                default:  
                    System.out.print("Invalid entry/n");  
            }//end switch  
        }//end while  
    }//end main()  
    public static String getString() throws IOException  
    {  
        InputStreamReader isr = new InputStreamReader(System.in);  
        BufferedReader br = new BufferedReader(isr);  
        String s = br.readLine();  
        return s;  
    }  
    public static char getChar() throws IOException  
    {  
        String s = getString();  
        return s.charAt(0);  
    }  
    public static int getInt() throws IOException  
    {  
        String s = getString();  
        return Integer.parseInt(s);  
    }  
}//end class TreeApp  
二叉树 BinaryTree （先序、中序、后序遍历 节点查找、插入、删除 完整类） Java数据结构与算法

二叉树 BinaryTree （先序、中序、后序遍历节点查找、插入、删除完整类） Java数据结构与算法
