Help on Reconstruction of Binary Tree

I have everything expect the reconstruct method and main method. Could someone help me create the reconstruct and main method?
package binarytree;
public class BinaryTree {
public BinaryTree(Object value, BinaryTree left, BinaryTree right){
          info = value;
          this.left = left;
          this.right = right;
     public Object getinfo(){
          return info;
     public BinaryTree getleft(){
return left;
public BinaryTree getright(){
return right;
     private Object info;
     private BinaryTree left, right;
     static int height (BinaryTree node){
          if (node != null){
return(int)(1+Math.max(height(node.getleft()), height(node.getright())));
return 0;
public static void traverseIn(BinaryTree node){
if (node == null) return;
traverseIn(node.getleft());
System.out.println(node.getinfo());
traverseIn(node.getright());
public static void traversePre(BinaryTree node){
if (node == null) return;
traversePre(node.getleft());
traversePre(node.getright());
System.out.println(node.getinfo());
public static void main(String[] args) {
//traverseIn = ("3 1 7 5 0 4 8 2 9 6");
//traversePre = ("0 1 3 5 7 2 4 8 6 9");
}

Dear useless ____,
Your request for us to finish your homework has been
submitted. Please idly stand by and allow up to 100
weeks for completion.Actually nvm I was looking around through the forum, and found how to construct a BinaryTree from one of your tips. Thanks warnerja.

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    // demonstrates binary tree
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    import java.util.*; // for Stack class
    import java.lang.Integer; // for parseInt()
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         public double dData; // data item
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              while(current.iData != key) // while no match,
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                   else // or go right?
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                        return null; // didn't find it
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    } // end if go left
    else // or go right?
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         public static void main(String[] args) throws IOException
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              double val1;
              String Line,Term;
              BufferedReader input;
              input = new BufferedReader (new FileReader ("one.txt"));
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    theTree.insert(43, 1.7);
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    theTree.insert(33, 1.2);
    theTree.insert(87, 1.7);
    theTree.insert(93, 1.5);
    theTree.insert(97, 1.5);
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              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)
                   putText("Enter first letter of ");
                   putText("show, insert, find, delete, or traverse: ");
                   int choice = getChar();
                   switch(choice)
                   case 's':
                        theTree.displayTree();
                        break;
                   case 'i':
                        putText("Enter value to insert: ");
                        value = getInt();
                        theTree.insert(value, value + 0.9);
                        break;
                   case 'f':
                        putText("Enter value to find: ");
                        value = getInt();
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                             putText("Found: ");
                             found.displayNode();
                             putText("\n");
                        else
                             putText("Could not find " + value + '\n');
                        break;
                   case 'd':
                        putText("Enter value to delete: ");
                        value = getInt();
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                        break;
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                        putText("Enter type 1, 2 or 3: ");
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                        theTree.traverse(value);
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                        putText("Invalid entry\n");
                   } // end switch
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              System.out.print(s);
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              int index = 0, len = 0;
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              while(index < len) {
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                    return t;
    }

    I don't know if this is a translation of your C code, but it can reconstruct any binary tree (with letters as nodes and no duplicates) from preorder and inorder traversals. Hope it helps.
    import java.util.*;
    public class ReconstructTree {
        public ReconstructTree() {
        public static void main(String[] args)
            String preorder = "ABDGKLRVWSXCEHMNFIOTUJPYQZ";
            String inorder = "KGVRWLSXDBAMHNECTOUIFPYJZQ";
            Map table = new HashMap();
            Map table2 = new HashMap();
            for(int i=0; i<inorder.length(); i++)
                table.put("" + inorder.charAt(i), new Integer(i));
                table2.put(new Integer(i), "" + inorder.charAt(i));
            List temppreorder = new ArrayList();
            for(int i=0; i<preorder.length(); i++)
                temppreorder.add(table.get("" + preorder.charAt(i)));
            Node root = constructTree(temppreorder);
            printPostOrder(root, table2);
        public static void printPostOrder(Node root, Map table)
            if(root == null)
                return;
            Node left = root.getLeft();
            Node right = root.getRight();
            printPostOrder(left, table);
            printPostOrder(right, table);
            System.out.print(table.get(new Integer(Integer.parseInt("" + root.getValue()))));
        public static Node constructTree(List preorder)
            Iterator it = preorder.iterator();
            int r = ((Integer)it.next()).intValue();
            Node root = new Node(r);
            Node node = root;
            while(it.hasNext())
                node = root;
                int a = ((Integer)it.next()).intValue();
                while(true)
                    r = node.getValue();
                    if(a < r)
                        if(node.getLeft() == null)
                            node.setLeft(new Node(a));
                            break;
                        else
                            node = node.getLeft();
                    else
                        if(node.getRight() == null)
                            node.setRight(new Node(a));
                            break;
                        else
                            node = node.getRight();
            return root;
        public static class Node
            private Node left = null;
            private Node right = null;
            private int value;
            public Node(int v)
                value = v;
            public int getValue()
                return value;
            public Node getLeft()
                return left;
            public Node getRight()
                return right;
            public void setLeft(Node l)
                left = l;
            public void setRight(Node r)
                right = r;
    }

  • Binary Tree Help

    I have a project where I need to build a binary tree with random floats and count the comparisons made. The problem I'm having is I'm not sure where to place the comaprison count in my code. Here's where I have it:
    public void insert(float idata)
              Node newNode = new Node();
              newNode.data = idata;
              if(root==null)
                   root = newNode;
              else
                   Node current = root;
                   Node parent;
                   while(true)
                        parent = current;
                        if(idata < current.data)
                             comp++;
                             current = current.leftc;
                             if(current == null)
                                  parent.leftc = newNode;
                                  return;
                        else
                             current = current.rightc;
                             if(current == null)
                                  parent.rightc = newNode;
                                  return;
         }//end insertDo I have it in the right place? Also, if I'm building the tree for 10,000 numbers would I get a new count for each level or would I get one count for comparisons?? I'd appreciate anyone's help on this.

    You never reset the comp variable, so each timeyou
    insert into the tree, it adds the number ofinserts
    to the previous value.Yes, or something like that. I'm not sure what theOP
    really means.Yeah, it's hard to be sure without seeing the rest of
    the code.Sorry, I thought I had already posted my code for you to look at.
    Here's a copy of it:
    class Node
         public float data;
         public Node leftc;
         public Node rightc;
    public class Btree
         private Node root;
         private int comp;
         public Btree(int value)
              root = null;
         public void insert(float idata)
              Node newNode = new Node();
              newNode.data = idata;
              if(root==null)
                   root = newNode;
              else
                   Node current = root;
                   Node parent;
                   while(true)
                        parent = current;
                        comp++;
                        if(idata < current.data)
                             current = current.leftc;
                             if(current == null)
                                  parent.leftc = newNode;
                                  return;
                        else
                             current = current.rightc;
                             if(current == null)
                                  parent.rightc = newNode;
                                  return;
         }//end insert
        public void display()
             //System.out.print();
             System.out.println("");     
             System.out.println(comp);
    } //end Btree
    class BtreeApp
         public static void main(String[] args)
              int value = 10000;
              Btree theTree = new Btree(value);
              for(int j=0; j<value; j++)
                   float n = (int) (java.lang.Math.random() *99);
                   theTree.insert(n);
                   theTree.display();
    }

  • Help loading a binary tree from file

    Hi all,
    So I am working on making a 20 question game using a binary tree. I have set it up so each time the user plays, if the computer cannot guess what they are thinking of, they tell the computer and it saves it. I am saving the tree in a text file recursively, in a format that looks something like this:
    Do you use it outside?
    a shovel
    [null]
    [null]
    is it round?
    a ball
    [null]
    [null]
    a TV
    [null]
    [null]
    The problem is now, I am having a very hard time rebuilding the tree when the user restarts the game. As you can see, the "{" indicates the beginning of a path and the "}" is the end. Can someone suggest a nice way to load this back up into my data structure? Thanks!!

    Cross-post here: [http://www.java-forums.org/java-2d/14237-help-loading-binary-tree-file.html]
    Recommended looking into XML

  • Problem with binary tree please help

    i am trying to make a binary tree but the problem is that when i print the data only the last value is printed i think i am moving my root. but dont know how to solve it please help me.
    public void insert(String n)
    //          (void)
              if (root == null)
                   System.out.println("Root is null");
                   TreeNode temp = new TreeNode(n);
                   System.out.println("\n\n\n\n"+temp.name+"\n\n\n\n\n");
                   root = rootTemp = temp;
              else
                   System.out.println("Root is not null" +rootTemp.name);
                   insert(rootTemp, n);
         private TreeNode insert(TreeNode v, String n) {
              if (v == null)
                   return new TreeNode(n);
              else
                   if (n.compareTo(v.name) < 0)
                        v.left = insert(v.left, n);
                   else
                        v.right = insert(v.right, n);
                   return v;
         }

    Are you sure the problem is not in the printing code?
    I can't see any obvious mistakes after a quick look... But if "root" is a reference to the root node, what is "rootTemp"?

  • Help with a binary tree

    I'm writing a binary tree class and am having some trouble with the Insert function. Here is the code for the TreeNode class...
    public class TreeNode
         TreeNode Left;
         TreeNode Right;
         String Name;
         public TreeNode(String NodeName)
              Left = null;
              Right = null;
              Name = NodeName;
    }And this is the code for the Tree class...
    public class Tree
         TreeNode Root;
         public Tree(String RootNode)
              Root = new TreeNode(RootNode);
         public void Insert(String Name)
              InsertNode(Root, Name);
         public void InsertNode(TreeNode t, String NodeName)
              if (t == null)
                   t = new TreeNode(NodeName);
              else
                   if (NodeName.compareTo(t.Name) < 0)
                        InsertNode(t.Left, NodeName);
                   else if (NodeName.compareTo(t.Name) > 0)
                        InsertNode(t.Right, NodeName);
                   else if (NodeName.compareTo(t.Name) == 0)
                        System.out.println("Entered node that was already in Tree");
    }When I enter a new node into a Tree containing just the root, it follows the recursion through once, then creates the new TreeNode as it should. However, the new node is not really recognized by the tree because when I try to insert another node, it only finds the root in the tree and only goes through one recursion. What's wrong?

    I believe t.Left (or t.Right) is getting set in the line
    t = new TreeNode(NodeName);
    Since it is a recursive function, when it is called the second time, the "t" that is passed in is actually the original t.left (I think), which is getting set then.

  • A Binary Tree Implementation in ABAP

    Hi,
    Can any one explaine me how to create a binary tree of random numbers with dynamic objects.
    Thanks,
    Manjula.

    Hi manjula,
    This sample code uses dynamic objects to create a binary tree of random numbers as per your requirement ...pls go through It. 
    It stores numbers on the left node or right node depending on the value comparison with the current value. There are two recursive subrotines used for the building of the tree and printing  through the tree.
    For comparison purpose, the same random numbers are stored and sorted in an internal table and printed.
    *& Report YBINTREE - Build/Print Binary Tree of numbers *
    report ybintree .
    types: begin of stree,
    value type i,
    left type ref to data,
    right type ref to data,
    end of stree.
    data: tree type stree.
    data: int type i.
    data: begin of rnd occurs 0,
    num type i,
    end of rnd.
    start-of-selection.
    do 100 times.
    generate random number between 0 and 100
    call function 'RANDOM_I4'
    exporting
    rnd_min = 0
    rnd_max = 100
    importing
    rnd_value = int.
    store numbers
    rnd-num = int.
    append rnd.
    build binary tree of random numbers
    perform add_value using tree int.
    enddo.
    stored numbers are sorted for comparison
    sort rnd by num.
    print sorted random numbers
    write: / 'Sorted Numbers'.
    write: / '=============='.
    skip.
    loop at rnd.
    write: rnd-num.
    endloop.
    skip.
    print binary tree. This should give the same result
    as the one listed from the internal table
    write: / 'Binary Tree List'.
    write: / '================'.
    skip.
    perform print_value using tree.
    skip.
    *& Form add_value
    text - Build tree with value provided
    -->TREE text
    -->VAL text
    form add_value using tree type stree val type i.
    field-symbols: <ltree> type any.
    data: work type stree.
    if tree is initial. "When node has no values
    tree-value = val. " assign value
    clear: tree-left, tree-right.
    create data tree-left type stree. "Create an empty node for left
    create data tree-right type stree. "create an empty node for right
    else.
    if val le tree-value. "if number is less than or equal
    assign tree-left->* to <ltree>. "assign the left node to fs
    call add_value recursively with left node
    perform add_value using <ltree> val.
    else. "if number is greater
    assign tree-right->* to <ltree>. "assign the right node to fs
    call add_value recursively with right node
    perform add_value using <ltree> val.
    endif.
    endif.
    endform. "add_value
    *& Form print_value
    text - traverse tree from left-mid-right order
    automatically this will be sorted list
    -->TREE text
    form print_value using tree type stree.
    field-symbols: <ltree> type any.
    if tree is initial. "node is empty
    else. "non-empty node
    assign tree-left->* to <ltree>. "left node
    perform print_value using <ltree>. "print left
    write: tree-value. "print the current value
    assign tree-right->* to <ltree>. "right node
    perform print_value using <ltree>. "print right
    endif.
    endform. "print_value
    pls reward if helps,
    regards.

  • Having trouble finding the height of a Binary Tree

    Hi, I have an ADT class called DigitalTree that uses Nodes to form a binary tree; each subtree only has two children at most. Each node has a "key" that is just a long value and is placed in the correct position on the tree determined by its binary values. For the height, I'm having trouble getting an accurate height. With the data I'm using, I should get a height of 5 (I use an array of 9 values/nodes, in a form that creates a longest path of 5. The data I use is int[] ar = {75, 37, 13, 70, 75, 90, 15, 13, 2, 58, 24} ). Here is my code for the whole tree. If someone could provide some tips or clues to help me obtain the right height value, or if you see anything wrong with my code, it would be greatly aprpeciated. Thanks!
    public class DigitalTree<E> implements Copyable
       private Node root;
       private int size;
       public DigitalTree()
           root = null;
           size = 0;
       public boolean add(long k)
           if(!contains(k))
                if(this.size == 0)
                    root = new Node(k);
                    size++;
                    System.out.println(size + " " + k);
                else
                    String bits = Long.toBinaryString(k);
                    //System.out.println(bits);
                    return add(k, bits, bits.length(), root);
                return true;
           else
               return false;
       private boolean add(long k, String bits, int index, Node parent)
           int lsb;
           try
               lsb = Integer.parseInt(bits.substring(index, index - 1));
           catch(StringIndexOutOfBoundsException e)
               lsb = 0;
           if(lsb == 0)
               if(parent.left == null)
                   parent.left = new Node(k);
                   size++;
                   //System.out.println(size + " " + k);
                   return true;
               else
                   return add(k, bits, index-1, parent.left);
           else
               if(parent.right == null)
                   parent.right = new Node(k);
                   size++;
                   //System.out.println(size + " " + k);
                   return true;
               else
                   return add(k, bits, index-1,  parent.right);
       public int height()
           int leftHeight = 0, rightHeight = 0;
           return getHeight(root, leftHeight, rightHeight);
       private int getHeight(Node currentNode, int leftHeight, int rightHeight)
           if(currentNode == null)
               return 0;
           //else
           //    return 1 + Math.max(getHeight(currentNode.right), getHeight(currentNode.left));
           if(currentNode.left == null)
               leftHeight = 0;
           else
               leftHeight = getHeight(currentNode.left, leftHeight, rightHeight);
           if(currentNode.right == null)
               return 1 + leftHeight;
           return 1 + Math.max(leftHeight, getHeight(currentNode.right, leftHeight, rightHeight));
       public int size()
           return size;
       public boolean contains(long k)
            String bits = Long.toBinaryString(k);
            return contains(k, root, bits, bits.length());
       private boolean contains(long k, Node currentNode, String bits, int index)
           int lsb;
           try
               lsb = Integer.parseInt(bits.substring(index, index - 1));
           catch(StringIndexOutOfBoundsException e)
               lsb = 0;
           if(currentNode == null)
               return false;
           else if(currentNode.key == k)
               return true;
           else
               if(lsb == 0)
                   return contains(k, currentNode.left, bits, index-1);
               else
                   return contains(k, currentNode.right, bits, index-1);
       public Node locate(long k)
            if(contains(k))
                String bits = Long.toBinaryString(k);
                return locate(k, root, bits, bits.length());
            else
                return null;
       private Node locate(long k, Node currentNode, String bits, int index)
           int lsb;
           try
               lsb = Integer.parseInt(bits.substring(index, index - 1));
           catch(StringIndexOutOfBoundsException e)
               lsb = 0;
           if(currentNode.key == k)
               return currentNode;
           else
               if(lsb == 0)
                   return locate(k, currentNode.left, bits, index-1);
               else
                   return locate(k, currentNode.right, bits, index-1);
       public Object clone()
           DigitalTree<E> treeClone = null;
           try
               treeClone = (DigitalTree<E>)super.clone();
           catch(CloneNotSupportedException e)
               throw new Error(e.toString());
           cloneNodes(treeClone, root, treeClone.root);
           return treeClone;
       private void cloneNodes(DigitalTree treeClone, Node currentNode, Node cloneNode)
           if(treeClone.size == 0)
               cloneNode = null;
               cloneNodes(treeClone, currentNode.left, cloneNode.left);
               cloneNodes(treeClone, currentNode.right, cloneNode.right);
           else if(currentNode != null)
               cloneNode = currentNode;
               cloneNodes(treeClone, currentNode.left, cloneNode.left);
               cloneNodes(treeClone, currentNode.right, cloneNode.right);
       public void printTree()
           System.out.println("Tree");
       private class Node<E>
          private long key;
          private E data;
          private Node left;
          private Node right;
          public Node(long k)
             key = k;
             data = null;
             left = null;
             right = null;
          public Node(long k, E d)
             key = k;
             data = d;
             left = null;
             right = null;
          public String toString()
             return "" + key;
    }

    You were on the right track with the part you commented out; first define a few things:
    1) the height of an empty tree is nul (0);
    2) the height of a tree is one more than the maximum of the heights of the left and right sub-trees.
    This translates to Java as a recursive function like this:
    int getHeight(Node node) {
       if (node == null) // definition #1
          return 0;   
       else // definition #2
          return 1+Math.max(getHeight(node.left), getHeight(node.right));
    }kind regards,
    Jos

  • Searching for a certain  binary tree from another tree........

    I have been struggling for a tree search problem for a good while. Now I decide to ask you experts for a better solution :-).
    Given a binary tree A. We know that every Node of A has two pointers. Leaves of A can be tested by if(node.right = =node). Namely, The right pointer of every leaf node points to itself. (The left pointer points to the node sits on the left side of the leaf in the same depth. and the leafmost node points to the root. I do no think this information is important, am i right?).
    Tree B has a similar structure.
    The node used for both A and B.
    Node{
    Node left;
    Node right;
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    So, the method should look like:
    public Node search(Node rootOfA, Node rootOfB){
    I know a simple recursive fuction can do the job. The question is all about the effciency....
    I am wonderring if this is some kind of well-researched problem and if there has been a classical solution.
    Anyone knows of that? Any friend can give a sound solution?
    Thank you all in advance.
    Jason
    Message was edited by:
    since81

    I'm not too sure if this would help but there goes.
    I think a recursive function will be the easiest to implement (but not the most efficient). In terms of recursive function if you really want to add performance. You could implement your own stack and replace the recursive function with the use of this stack (since really the benefit of recursive function is that it manages its own stack). A non-recursive function with customized well implemented stack will be much more efficient but your code will become more ugly too (due to so many things to keep track of).
    Is tree B a separate instance of the binary tree? If yes then how can Tree B be a subset/subtree of tree A (since they are two separate "trees" or instances of the binary tree). If you wish to compare the data /object reference of Tree B's root node to that of Tree A's then the above method would be the most efficient according to my knowledge. You might have to use a Queue but I doubt it. Stack should be able to replace your recursive function to a better more efficient subroutine but you will have to manage using your own stack (as mentioned above). Your stack will behave similar to the recursive stack to keep track of the child/descendant/parent/root node and any other references that you may use otherwise.
    :)

  • Binary Tree in Java - ******URGENT********

    HI,
    i want to represent a binary tree in java. is there any way of doing that.
    thanx
    sraphson

    HI,
    i want to represent a binary tree in java. is there
    e any way of doing that.
    thanx
    sraphsonFirst, what is a binary tree? Do you know how the binary tree looks like on puesdo code? How about a representation in terms of numbers? What is a tree? What is binary? The reason I ask is, what do you know about programming?
    Asking to represent a binary tree in java seems like a question who doesn't know how it looks like in the first please. Believe me, I am one of them. I am not at this level yet. If you are taking a class that is teaching binary trees and you don't know how it looks like, go back to your notes.
    Sounds harsh, but it is better to hear it from a person that doesn't know either then a boss that hired you because Computer Science was what you degree said. Yet, you don't know how to program?
    Telling you will not help you learn. I can show you tutorials of trees would be start on where to learn.
    HOW TO USE TREES (oops this is too simple, but it is a good example)
    http://java.sun.com/docs/books/tutorial/uiswing/components/tree.html
    CS312 Data Structures and Analysis of Algorithms
    (Here is a course about trees. Search and learn)
    http://www.calstatela.edu/faculty/jmiller6/cs312-winter2003/index.htm

  • How to design  databse for binary tree

    kindly help in desiging databse for binary tree and also to retrive data from database.

    Since you're not asking about Java, you'll probably get more responses by posting this in a database forum.

  • Binary Tree search and print methods

    Hello, I'm trying to create a binary tree from inputs of a user. I believe I have the tree set up right because it shows no errors, but I'm getting an error message with a line of code. I cannot figure out what I am doing wrong. Also, I need to create a print method, which prints the tree's entries and a search method which would search the tree for certain record.
    public class TreeNode 
          public static String empName = null;
          public static int empNumber;
          public static String nextRec = null;
              TreeNode left;
          String Name;
          int Number;
          TreeNode right;
          public static void main(String[] args)
             VRead in = new VRead();
             VWrite out = new VWrite();
             System.out.println("Enter Choice: ");
             System.out.println("A: Enter Employee Information.");
             System.out.println("B: Search For Employee.");
             System.out.println("C: Print Entire Tree.");
             System.out.println("D: Exit.");
             System.out.println("_______________________________");
             char command = in.readChar();
             System.out.println();
             switch (command)
                case 'A':
                case 'a':
                   inputInfo(in, out);           
                   break;
                case 'B':
                case 'b':
                   break;
                case 'C':
                case 'c':
                   break;
                case 'D':
                case 'd':
                   System.exit(0);
                   break;
          public static void inputInfo(VRead in, VWrite out)
             out.write("Enter Employee Name: ");
             empName = in.readString();
             out.write("Enter Employee Number: ");
             empNumber = in.readInt();
             System.out.println();
             System.out.println();
             System.out.println("Enter Choice: ");
             System.out.println("A: Enter Employee Information.");
             System.out.println("B: Search For Employee.");
             System.out.println("C: Print Entire Tree.");
             System.out.println("D: Exit.");
             System.out.println("_______________________________");
             char command = in.readChar();
             System.out.println();
             switch (command)
                case 'A':
                case 'a':
                   inputInfo(in, out);           
                   break;
                case 'B':
                case 'b':
                   break;
                case 'C':
                case 'c':
                             break;
                case 'D':
                case 'd':
                   System.exit(0);
                   break;
          public TreeNode(String empName, int empNumber)
             Name = empName;
             Number = empNumber;
             left = null;
             right = null;
          public class Tree
             TreeNode Root;
             public void Tree(String RootNode)   
        // Errors come from next line
                  Root = new TreeNode(RootNode, Name, Number);   
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