二叉树之插入查找
1、什么是二叉树
在计算机科学中,二叉树是每个节点最多有两个子树的树结构。通常子树被称作“左子树”(left subtree)和“右子树”(right subtree)。
2、源码
1)Node节点
public class Node {
int data;
Node leftChile;
Node rightChile;
public Node() {
super();
// TODO Auto-generated constructor stub
}
public Node(int data) {
super();
this.data = data;
}
public Node(int data, Node leftChile, Node rightChile) {
super();
this.data = data;
this.leftChile = leftChile;
this.rightChile = rightChile;
}
}
2)Tree:
public class Tree {
private Node root;
public Node getRoot() {
return root;
}
public void setRoot(Node root) {
this.root = root;
}
public void insert(int data) {
Node currentNode = root;
if(null == currentNode) {
currentNode = new Node(data);
root = currentNode;
}else {
while(true) {
if(currentNode.data > data) {
if(null != currentNode.leftChile) {
currentNode = currentNode.leftChile;
}else {
currentNode.leftChile = new Node(data);
break;
}
}else {
if(null != currentNode.rightChile) {
currentNode = currentNode.rightChile;
}else {
currentNode.rightChile = new Node(data);
break;
}
}
}
}
}
public Node find(int data) {
Node currentNode = root;
boolean flag = true;
if(null == currentNode) {
return null;
}else {
if(currentNode.data == data) {
return currentNode;
}else {
while(flag) {
if(currentNode.data != data && null == currentNode.leftChile && null == currentNode.rightChile) {
flag = false;
return null;
}else {
if(currentNode.data > data && null != currentNode.leftChile) {
currentNode = currentNode.leftChile;
}else if(currentNode.data < data && null != currentNode.rightChile){
currentNode = currentNode.rightChile;
}else if(currentNode.data == data) {
flag = false;
return currentNode ;
}else {
currentNode = null;
}
}
}
}
}
return currentNode;
}
}
3)测试程序
public class TreeApp {
public static void main(String[] args) {
Tree t = new Tree();
t.insert(50);
t.insert(30);
t.insert(20);
t.insert(60);
t.insert(65);
t.insert(35);
t.insert(55);
}
}
Reference:
[1] Robert Lafore(著), 计晓云, 赵研, 曾希, 狄小菡(译), Java数据结构和算法(第二版), 中国电力出版社, 2004:287-288