所实现的功能为
insert 插入
del 删除
find 查找
getMin 查找最小值
getMax 查找最大值
size 结点总个数
getHeight 树的高度
inorder 中序遍历
[前序遍历和后序遍历请看我之前文章] 144. 二叉树的前序迭代遍历推出后序，中序以及层序的实现
printleaves 打印叶子结点
onelevelnum 打印树的每一层结点
kthlargest 树的第k最大值
suojin 缩进打印树
所有的功能对应大部分至少两种方法
BitreeNode 类 代码如下
package BST;
class BiTreeNode {
public BiTreeNode lchild, rchild;
public int data;
public BiTreeNode(int data) {
this.data=data;
}
public BiTreeNode() {
lchild=rchild=null;
data=0;
}
@Override
public String toString() {
return "BiTreeNode [data=" + data + "]";
}
public BiTreeNode(BiTreeNode lchild, BiTreeNode rchild, int data) {
this.lchild = lchild;
this.rchild = rchild;
this.data = data;
}
}
BiSearchTree 类 代码如下
package BST;
import java.util.LinkedList;
import java.util.Queue;
import java.util.Stack;
public class BiSearchTree {
public BiTreeNode root;
int m = 0;
int n;
public BiSearchTree() {
root = null;
}
public void insert(int x) {
if (root == null) {
root = new BiTreeNode(x);
return;
}
BiTreeNode p = root;
while (p != null) {
if (x > p.data) {
if (p.rchild == null) {
p.rchild = new BiTreeNode(x);
return;
}
p = p.rchild;
} else {
if (p.lchild == null) {
p.lchild = new BiTreeNode(x);
return;
}
p = p.lchild;
}
}
}
public BiTreeNode insert2(BiTreeNode p, int x) {
if (root == null) {
root = new BiTreeNode(x);
}
if (p == null) {
p = new BiTreeNode(x);
return p;
} else {
if (x > p.data) {
p.rchild = insert2(p.rchild, x);
} else if (x < p.data) {
p.lchild = insert2(p.lchild, x);
}
return p;
}
}
public void del1(int x) {
BiTreeNode p = root;
BiTreeNode parent = p;
while (p != null && p.data != x) {
parent = p;
if (x > p.data) {
p = p.rchild;
} else {
p = p.lchild;
}
}
if (p == null) {
System.out.println("error");
return;
} else if (p.data == x) {
if (p.lchild != null && p.rchild != null) {
BiTreeNode temp = p;
BiTreeNode parent2 = temp;
temp = p.lchild;
p.data = getMax2(temp).data;
while (temp.rchild != null) {
parent2 = temp;
temp = temp.rchild;
}
if (temp.lchild == null) {
if (parent2.lchild == temp) {
parent2.lchild = null;
} else {
parent2.rchild = null;
}
} else {
if (parent2.lchild == temp) {
parent2.lchild = temp.lchild;
} else {
parent2.rchild = temp.lchild;
}
}
} else {
BiTreeNode child;
if (p.lchild != null) {
child = p.lchild;
} else if (p.rchild != null) {
child = p.rchild;
} else {
child = null;
}
if (parent.lchild == p) {
parent.lchild = child;
} else if (parent.rchild == p) {
parent.rchild = child;
} else {
root = child;
}
}
}
}
public BiTreeNode del2(BiTreeNode p, int x) {
if (p == null) {
System.out.println("empty error");
return p;
}
if (x < p.data) {
p.lchild = del2(p.lchild, x);
} else if (x > p.data) {
p.rchild = del2(p.rchild, x);
} else {
if (p.lchild != null && p.rchild != null) {
BiTreeNode temp = p.lchild;
p.data = getMax2(temp).data;
p.lchild = del2(p.lchild, p.data);
} else if (p.lchild == null) {
p = p.rchild;
} else if (p.rchild == null) {
p = p.lchild;
}
}
root = p;
return p;
}
public void del3(int x) {
BiTreeNode p = root;
BiTreeNode parent = p;
while (p != null && p.data != x) {
parent = p;
if (x < p.data) {
p = p.lchild;
} else if (x > p.data) {
p = p.rchild;
}
}
if (p == null) {
return;
} else {
if (p.lchild != null && p.rchild != null) {
BiTreeNode temp = p.lchild;
if (parent.lchild == p) {
parent.lchild = temp;
} else if (parent.rchild == p) {
parent.rchild = temp;
} else {
if (p.lchild != null) {
root = p.lchild;
} else if (p.rchild != null) {
root = p.rchild;
}
}
getMax2(temp).rchild = p.rchild;
} else {
BiTreeNode child = null;
if (p.lchild != null) {
child = p.lchild;
} else if (p.rchild != null) {
child = p.rchild;
}
if (parent.lchild == p) {
parent.lchild = child;
} else if (parent.rchild == p) {
parent.rchild = child;
} else {
root = child;
}
}
}
}
public BiTreeNode del4(BiTreeNode p, int x) {
if (p == null) {
return p;
}
if (x < p.data) {
p.lchild = del4(p.lchild, x);
} else if (x > p.data) {
p.rchild = del4(p.rchild, x);
} else {
if (p.lchild != null && p.rchild != null) {
BiTreeNode temp = getMax2(p.lchild);
temp.rchild = p.rchild;
p = p.lchild;
} else if (p.lchild == null) {
p = p.rchild;
} else if (p.rchild == null) {
p = p.lchild;
}
}
root = p;
return p;
}
public BiTreeNode find(int x) {
BiTreeNode p = root;
if (p == null) {
System.out.println("empty error");
return p;
}
while (p != null) {
if (x > p.data) {
p = p.rchild;
} else if (x < p.data) {
p = p.lchild;
} else {
return p;
}
}
return null;
}
public BiTreeNode find2(BiTreeNode p, int x) {
if (p == null) {
System.out.println("empty error");
return p;
}
if (x > p.data) {
return find2(p.rchild, x);
} else if (x < p.data) {
return find2(p.lchild, x);
} else {
if (x == p.data) {
return p;
} else {
return null;
}
}
}
public BiTreeNode getMin() {
if (root == null) {
return null;
}
BiTreeNode p = root;
while (p.lchild != null) {
p = p.lchild;
}
return p;
}
public BiTreeNode getMin2(BiTreeNode p) {
if (p == null) {
System.out.println("error p结点data为空");
return null;
}
if (p.lchild == null) {
return p;
}
return getMin2(p.lchild);
}
public BiTreeNode getMax() {
if (root == null) {
return null;
}
BiTreeNode p = root;
while (p.rchild != null) {
p = p.rchild;
}
return p;
}
public BiTreeNode getMax2(BiTreeNode p) {
if (p == null) {
System.out.println("error p结点data为空");
return null;
}
if (p.rchild == null) {
return p;
}
return getMax2(p.rchild);
}
public int size() {
return size(root);
}
public int size(BiTreeNode p) {
if (p == null) {
return 0;
}
return 1 + size(p.lchild) + size(p.rchild);
}
public void size2(BiTreeNode p) {
int num=1;
Queue<BiTreeNode> queue = new LinkedList<BiTreeNode>();
queue.add(p);
while(!queue.isEmpty()) {
BiTreeNode temp=queue.poll();
if(temp.lchild!=null) {
queue.add(temp.lchild);
num++;
}
if(temp.rchild!=null) {
queue.add(temp.rchild);
num++;
}
}
System.out.println(num);
}
public int getHeight() {
return getHeight(root);
}
public int getHeight(BiTreeNode p) {
if (p == null) {
return 0;
}
return getHeight(p.lchild) > getHeight(p.rchild) ? getHeight(p.lchild) + 1 : getHeight(p.rchild) + 1;
}
public int getHeight2() {
return getHeight2(root);
}
public int getHeight2(BiTreeNode p) {
int height=0;
Queue<BiTreeNode> queue = new LinkedList<BiTreeNode>();
queue.add(p);
while(!queue.isEmpty()) {
int n=queue.size();
for(int i=0;i<n;i++) {
BiTreeNode temp=queue.poll();
if(temp.lchild!=null) {
queue.add(temp.lchild);
}
if(temp.rchild!=null) {
queue.add(temp.rchild);
}
}
height++;
}
return height;
}
public int inorder(BiTreeNode p) {
if (p == null) {
return -1;
}
inorder(p.lchild);
System.out.print(p.data + " ");
inorder(p.rchild);
return 1;
}
public int inorder() {
return inorder(root);
}
public LinkedList<Integer> inorder2() {
if (root == null) {
return null;
}
BiTreeNode p = root;
LinkedList<Integer> list = new LinkedList<Integer>();
Stack<BiTreeNode> stack = new Stack<BiTreeNode>();
while (p != null || !stack.isEmpty()) {
if (p != null) {
stack.push(p);
p = p.lchild;
} else {
p = stack.pop();
list.addLast(p.data);
p = p.rchild;
}
}
System.out.println(list.toString());
return list;
}
public void OneLevelnum(int xlevel) {
BiTreeNode p=root;
int height=0;
Queue<BiTreeNode> queue = new LinkedList<BiTreeNode>();
queue.add(p);
while(!queue.isEmpty()) {
int n=queue.size();
if(++height==xlevel) {
for(int i=0;i<n;i++) {
System.out.print(queue.poll()+" ");
}
break;
}
for(int i=0;i<n;i++) {
BiTreeNode temp=queue.poll();
if(temp.lchild!=null) {
queue.add(temp.lchild);
}
if(temp.rchild!=null) {
queue.add(temp.rchild);
}
}
}
}
public void printleaves(BiTreeNode p) {
if (p == null)
return;
if (p.lchild == null && p.rchild == null) {
System.out.print(p + " ");
} else {
printleaves(p.lchild);
printleaves(p.rchild);
}
}
public void printleaves2(BiTreeNode p) {
int height=getHeight();
OneLevelnum(height);
}
public void suojin() {
suojin(root, 1);
}
public void suojin(BiTreeNode p, int i) {
if (p == null)
return;
else {
for (int j = 0; j < i; j++) {
System.out.print("-");
}
System.out.println(p.data);
suojin(p.lchild, ++i);
i--;
suojin(p.rchild, ++i);
i--;
}
}
public int kthLargest(BiTreeNode p, int k) {
if (p == null) {
return -1;
}
kthLargest(p.rchild, k);
m++;
if (k == m) {
n = p.data;
return p.data;
}
kthLargest(p.lchild, k);
return n;
}
}