java :非递归方法的二叉搜索树，实现部分功能

//

//实现了如下功能

public class BinarySearchTree {

/**
*
* @author Administrator
*嵌套类构造结点
* @param <Integer>
*/
private static class BinaryNode<Integer>{
public Integer data;
public BinaryNode<Integer> lchild;
public BinaryNode<Integer> rchild;

public BinaryNode(Integer d,BinaryNode<Integer> l,BinaryNode<Integer> r){
this.data = d;
this.lchild = l;
this.rchild = r;
}
}

//根节点
private BinaryNode<Integer> root;

public BinarySearchTree(){
root = null;
}

/**
* 返回根节点
* @param x
* @param r
* @return
*/
public BinaryNode<Integer> add(Integer x,BinaryNode<Integer> r){
BinaryNode<Integer> tmp = r;
BinaryNode<Integer> p = new BinaryNode<Integer>(x,null,null);
if(r == null){
r = p;
}else{
while(tmp.lchild!=p && tmp.rchild != p){
if(x<tmp.data){
if(tmp.lchild == null){
tmp.lchild = p;
}else{
tmp = tmp.lchild;
}
}else if(x>tmp.data){
if(tmp.rchild == null){
tmp.rchild = p;
}else{
tmp = tmp.rchild;
}
}

}

}

return r;
}

/**
* 返回最小的结点
* @param r
* @return
*/
public BinaryNode<Integer> findMin(BinaryNode<Integer> r){
if(r != null){
while(r.lchild != null){
r = r.lchild;
}
}

return r;
}

/**
* 返回最大的结点
* @param r
* @return
*/
public BinaryNode<Integer> findMax(BinaryNode<Integer> r){
if(r != null){
while(r.rchild != null){
r = r.rchild;
}
}

return r;
}

//删除一个节点
public BinaryNode<Integer> remove(Integer x,BinaryNode<Integer> r){
BinaryNode<Integer> tmp = r;
BinaryNode<Integer> p = null ;//指示目标结点的父亲
if(r == null){
throw new NullPointerException();
}

while(tmp.data != x){
if(x<tmp.data){
p = tmp;
tmp = tmp.lchild;
}else if(x<tmp.data){
p = tmp;
tmp = tmp.rchild;
}
}
//如果待删结点是叶子结点
if(tmp.lchild == null && tmp.rchild == null){
if(tmp == r){
tmp = null; //若为根节点，将根节点置空
}else if(p.lchild == tmp){
p.lchild = null;
}else{
p.rchild = null;
}
}else

//如果为单叶子结点
if(tmp.lchild == null || tmp.rchild == null){
if(tmp == r){
if(tmp.lchild == null){
tmp = tmp.rchild;
}else if(tmp.rchild == null){
tmp = tmp.lchild;
}
}else

if(p.lchild == tmp){
if(tmp.lchild == null){
p.lchild = tmp.rchild;
}else if(tmp.rchild == null){
p.lchild = tmp.lchild;
}
} else if(p.rchild == tmp){
if(tmp.lchild == null){
p.lchild = tmp.rchild;
}else if(tmp.rchild == null){
p.lchild = tmp.lchild;
}
}
}else {//目标结点的子结点都不为空
BinaryNode<Integer> a = tmp ;
BinaryNode<Integer> b = tmp.rchild ;

while(b.lchild != null){//选右边数最小的数据
a = b;
b = b.lchild;
}

tmp.data = b.data;
if(a == tmp){
tmp.rchild = b.rchild;//若目标结点的右子结点没有左子节点
}else{
a.lchild = b.rchild;
}

}
return r;
}
}