package com.test;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Stack;
/**
*
* @author hf
* @email [email protected]
* @since 2010-11-10
* @version 1.0
*
*/
class Node
{
public int iData; //Data item(key)
public Double dData; //Data item
public Node leftChild; //this Node leftChild
public Node rightChild; //this Node rightChild
public void displayNode() //display ourself
{
System.out.print("{");
System.out.print(iData);
System.out.print("}");
System.out.print("{");
System.out.print(dData);
System.out.print("}");
}
}//end class Node
class Tree
{
private Node root; //first node of tree
public Tree() //constructor
{
root = null; //no nodes in tree yet
}
public Node find(int key) //find node with given key
{ //(assumes non-empty tree)
Node current = root; //start at root
while(current.iData!=key) //while no much
{
if(key<current.iData) //go left
current = current.leftChild;
else //or go right
current = current.rightChild;
if(current==null) //if no child
return null; //didn't find it
}
return current; //found it
} //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 //root occupied
{
Node current = root; //start at root
Node parent;
while(true) //(exsit internally)
{
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
{ //insert on right
parent.rightChild = newNode;
return;
}
} //end else go right
}//end while
} //end else no root
} //end insert()
public boolean delete(int key) //delete Node with given key
{ //(assumes non-empty tree)
Node current = root;
Node parent = root;
boolean isLeftChild = true;
while(current.iData != key) //search for node
{
parent = current;
if(key <current.iData) //go left?
{
isLeftChild = true;
current = current.leftChild;
}
else //or go right
{
isLeftChild = false;
current = current.rightChild;
}
if(current ==null) //end of the line
return false; //didn't find it
}//end while
//found Node to delete
//if no children,simple delete it
if(current.leftChild==null&¤t.rightChild==null)
{
if(current==root) //if root
current = null; //tree is empty
else if(isLeftChild)
parent.leftChild = null; //disconnect
else //from parent
parent.rightChild = null;
}
//if no right children,replace with left subtree
else if(current.rightChild==null)
{
if(current==root)
root = current.rightChild;
else if(isLeftChild)
parent.leftChild = current.leftChild;
else
parent.rightChild = current.leftChild;
}
//if not left children,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;
}
else //two children,so replace with inOrder successor
{
//get successor of node to delete(current)
Node successor = getSuccessor(current);
//connect parent of current to successor instead
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 can not hava a left child)
return true; //success
}//end delete()
//returns node with next-highest value after delNode
//go 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) //util no more
{ //left children,
successorParent = successor;
successor = current;
current = current.leftChild; //go to left child
}
//if successor not
if(successor!=delNode.rightChild) //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.println("\nPreorder traversal: ");
preOrder(root);
break;
case 2:
System.out.println("\nInorder traversal: ");
inOrder(root);
break;
case 3:
System.out.println("\nPostorder traversal: ");
postOrder(root);
break;
}
System.out.println();
}
private void preOrder(Node localRoot)
{
if(localRoot!=null)
{
System.out.println(localRoot.iData+" ");
preOrder(localRoot.leftChild);
preOrder(localRoot.rightChild);
}
}
private void inOrder(Node localRoot)
{
if(localRoot!=null)
{
inOrder(localRoot.leftChild);
System.out.println(localRoot.iData+" ");
inOrder(localRoot.rightChild);
}
}
private void postOrder(Node localRoot)
{
if(localRoot!=null)
{
postOrder(localRoot.leftChild);
postOrder(localRoot.rightChild);
System.out.println(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 is not enmpty
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, ");
System.out.print("insert,find,delete, or traverse: ");
int chiose = getChar();
switch (chiose) {
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 the value to delete: ");
value = getInt();
boolean didDelete = theTree.delete(value);
if(didDelete)
System.out.print("Delete"+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");
break;
}
}
}
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);
}
}
