其中二叉树节点类
/** 二叉树节点 */
public class BTNode {
private char key;
private BTNode left, right;
public BTNode(char key) {
this(key, null, null);
}
public BTNode(char key, BTNode left, BTNode right) {
this.key = key;
this.left = left;
this.right = right;
}
public char getKey() {
return key;
}
填写下面表单即可预约申请免费试听java课程!害怕学不会?助教陪读，随时解惑!担心就业?一地学习，可全国推荐就业!
public void setKey(char key) {
this.key = key;
}
public BTNode getLeft() {
return left;
}
public void setLeft(BTNode left) {
this.left = left;
}
public BTNode getRight() {
return right;
}
public void setRight(BTNode right) {
this.right = right;
}
}
遍历二叉树
/** 二叉树遍历 */
public class BinTree {
protected BTNode root;
public BinTree(BTNode root) {
this.root = root;
}
public BTNode getRoot() {
return root;
}
/** 构造树 */
public static BTNode init() {
BTNode a = new BTNode('A');
BTNode b = new BTNode('B', null, a);
BTNode c = new BTNode('C');
BTNode d = new BTNode('D', b, c);
BTNode e = new BTNode('E');
BTNode f = new BTNode('F', e, null);
BTNode g = new BTNode('G', null, f);
BTNode h = new BTNode('H', d, g);
return h;// root
}
/** 访问节点 */
public static void visit(BTNode p) {
System.out.print(p.getKey() + " ");
}
/** 递归实现前序遍历 */
protected static void preorder(BTNode p) {
if (p != null) {
visit(p);
preorder(p.getLeft());
preorder(p.getRight());
}
}
/** 递归实现中序遍历 */
protected static void inorder(BTNode p) {
if (p != null) {
inorder(p.getLeft());
visit(p);
inorder(p.getRight());
}
}
/** 递归实现后序遍历 */
protected static void postorder(BTNode p) {
if (p != null) {
postorder(p.getLeft());
postorder(p.getRight());
visit(p);
}
}
/** 非递归实现前序遍历 */
protected static void iterativePreorder(BTNode p) {
Stack stack = new Stack();
if (p != null) {
stack.push(p);
while (!stack.empty()) {
p = stack.pop();
visit(p);
if (p.getRight() != null)
stack.push(p.getRight());
if (p.getLeft() != null)
stack.push(p.getLeft());
}
}
}
/** 非递归实现后序遍历 */
protected static void iterativePostorder(BTNode p) {
BTNode q = p;
Stack stack = new Stack();
while (p != null) {
// 左子树入栈
for (; p.getLeft() != null; p = p.getLeft())
stack.push(p);
// 当前节点无右子或右子已经输出
while (p != null && (p.getRight() == null || p.getRight() == q)) {
visit(p);
q = p;// 记录上一个已输出节点
if (stack.empty())
return;
p = stack.pop();
}
// 处理右子
stack.push(p);
p = p.getRight();
}
}
/** 非递归实现中序遍历 */
protected static void iterativeInorder(BTNode p) {
Stack stack = new Stack();
while (p != null) {
while (p != null) {
if (p.getRight() != null)
stack.push(p.getRight());// 当前节点右子入栈
stack.push(p);// 当前节点入栈
p = p.getLeft();
}
p = stack.pop();
while (!stack.empty() && p.getRight() == null) {
visit(p);
p = stack.pop();
}
visit(p);
if (!stack.empty())
p = stack.pop();
else
p = null;
}
}
public static void main(String[] args) {
BinTree tree = new BinTree(init());
System.out.print(" Pre-Order:");
preorder(tree.getRoot());
System.out.println();
System.out.print(" In-Order:");
inorder(tree.getRoot());
System.out.println();
System.out.print("Post-Order:");
postorder(tree.getRoot());
System.out.println();
System.out.print(" Pre-Order:");
iterativePreorder(tree.getRoot());
System.out.println();
System.out.print(" In-Order:");
iterativeInorder(tree.getRoot());
System.out.println();
System.out.print("Post-Order:");
iterativePostorder(tree.getRoot());
System.out.println();
}
}
输出结果
Pre-Order:H D B A C G F E
In-Order:B A D C H G E F
Post-Order:A B C D E F G H
Pre-Order:H D B A C G F E
In-Order:B A D C H G E F
Post-Order:A B C D E F G H
如果你现在想学习Java，赢取高薪工作机会，非常简单，填写下面信息，学好Java技术高薪工作机会唾手可得。
下一篇： 没有了
一级建造师二级建造师消防工程师造价工程师土建职称房地产经纪人公路检测工程师建筑八大员注册建筑师二级造价师监理工程师咨询工程师房地产估价师 城乡规划师结构工程师岩土工程师安全工程师设备监理师环境影响评价土地登记代理公路造价师公路监理师化工工程师暖通工程师给排水工程师计量工程师
执业药师执业医师卫生资格考试卫生高级职称护士资格证初级护师主管护师住院医师临床执业医师临床助理医师中医执业医师中医助理医师中西医医师中西医助理口腔执业医师口腔助理医师公共卫生医师公卫助理医师实践技能内科主治医师外科主治医师中医内科主治儿科主治医师妇产科医师西药士/师中药士/师临床检验技师临床医学理论中医理论
