二叉搜索树实例练习

import java.util.Scanner;
public class Main{
public static void main(String args[]){
Scanner in=new Scanner(System.in);
BinarySearchTree<Character> root=null;
while(in.hasNext()){
int t=in.nextInt();
if(t==0) break;
root=new BinarySearchTree<Character>();
String result=null;
String result1=null;
String s=in.next();
for(int i=0;i<s.length();i++){
root.insert(s.charAt(i));
}
result=root.printTree(root.getRoot());
for(int i=0;i<t;i++){
root=new BinarySearchTree<Character>();
s=in.next();
for(int j=0;j<s.length();j++){
root.insert(s.charAt(j));
}
result1=root.printTree(root.getRoot());
if(result.equals(result1)) System.out.println("YES");
else System.out.println("NO");
}
}
}
}
class BinaryNode< T extends Comparable<T>> {//二叉查找树节点
BinaryNode< T> left;
BinaryNode< T> right;
T element;
public BinaryNode(T theElement){
this(theElement, null, null);
}
public BinaryNode(T theElement, BinaryNode lt, BinaryNode rt){
element = theElement;
left = lt;
right = rt;
}
public T getElement(){
return this.element;
}
public BinaryNode< T> getLeft(){
return this.left;
}
public BinaryNode< T> getRight(){
return this.right;
}
public String toString(){
return element + "";
}
}
class BinarySearchTree< T extends Comparable<T>>{//二叉搜索树
private BinaryNode< T> root;//根节点
public BinarySearchTree(){//构造函数
root = null;
}
public BinarySearchTree(BinaryNode< T> t){//构造函数
root = t;
}
public void makeEmpty(){
root = null;
}
public boolean isEmpty(){
return root == null;
}
public BinaryNode<T> getRoot(){
return root;
}
public T find(T x){
return find(x, root).element;
}
public void insert(T x){
root = insert(x, root);
}
public void printTree(){
printTree(root);
}
private BinaryNode< T> find(T x, BinaryNode< T> t){//查找操作
if(t == null){
return null;
}
if(x.compareTo(t.element) < 0){
return find(x, t.left);
}
else if(x.compareTo(t.element) == 0){
return t;
}
else{
return find(x, t.right);
}
}
private BinaryNode< T> insert(T x, BinaryNode< T> t){//插入操作
if(t == null){
t = new BinaryNode< T>(x, null, null);
}
else if(x.compareTo(t.element) < 0){
t.left = insert(x, t.left);
}
else if(x.compareTo(t.element) > 0){
t.right = insert(x, t.right);
}
else;
return t;
}
private StringBuffer sb=new StringBuffer();
public String printTree(BinaryNode< T> t){//前序遍历二叉查找树
if(t != null){
sb.append(t.element);
printTree(t.left);
printTree(t.right);
}
return sb.toString();
}
}