package algorithm.linkedlist;
/**
* @Created by XDarker
* @Description Java实现单链表的增删改查
* @Date 2019/10/12 22:22
*/
public class LinkedListDemo {
public static void main(String[] args) {
// HeroNode node1 = new HeroNode("A");
// HeroNode node2 = new HeroNode("B");
// HeroNode node3 = new HeroNode("C");
// HeroNode node4 = new HeroNode("D");
//
// SingleLinkedList singleLinkedList = new SingleLinkedList();
// singleLinkedList.add(node1);
// singleLinkedList.add(node2);
// singleLinkedList.add(node3);
// singleLinkedList.add(node4);
HeroNode node1 = new HeroNode(1,"A");
HeroNode node2 = new HeroNode(3,"B");
HeroNode node3 = new HeroNode(5,"C");
HeroNode node4 = new HeroNode(7,"D");
SingleLinkedList singleLinkedList = new SingleLinkedList();
singleLinkedList.addByNum(node1);
singleLinkedList.addByNum(node4);
singleLinkedList.addByNum(node2);
singleLinkedList.addByNum(node3);
singleLinkedList.list();
HeroNode newHeroNode = new HeroNode(3,"BBB");
singleLinkedList.update(newHeroNode);
System.out.println("==========修改之后==========");
singleLinkedList.list();
System.out.println("==========删除之后==========");
singleLinkedList.delete(newHeroNode);
singleLinkedList.list();
}
}
class SingleLinkedList{
//初始化头节点
private HeroNode head = new HeroNode("");
/**
* 添加链表节点
* @param heroNode
*/
public void add(HeroNode heroNode){
HeroNode temp = head;
//遍历链表, 找到最后
while(true){
if (temp.next == null){
break;
}
temp = temp.next;
}
//退出循环时 temp指向了链表的最后
temp.next = heroNode;
}
/**
* 根据排位添加链表节点
* 如果排位已经存在则添加失败
* @param heroNode
*/
public void addByNum(HeroNode heroNode){
HeroNode temp = head;
//标志添加的编号是否存在 默认false
boolean flag = false;
while (true){
//说明temp已经到链表最后
if (temp.next == null){
break;
}
//位置找到, 在temp后加入
if (temp.next.num > heroNode.num){
break;
//说明排位已经存在
}else if(temp.next.num == heroNode.num){
flag = true;
break;
}
temp = temp.next;
}
if (flag){
System.out.printf("添加的链表排位 %d 已经存在, 不能加入\n", heroNode.num);
}else {
heroNode.next = temp.next;
temp.next = heroNode;
}
}
/**
* 根据 num 修改节点
* @param newHeroNode
*/
public void update(HeroNode newHeroNode){
if (head.next == null){
System.out.println("链表为空");
return;
}
HeroNode temp = head;
//表示是否找到该节点
boolean flag = false;
while(true){
//说明temp已经到链表最后
if (temp.next == null){
break;
}
if (temp.num == newHeroNode.num){
//找到
flag = true;
break;
}
temp = temp.next;
}
if (flag){
temp.name = newHeroNode.name;
}else {
System.out.printf("该排位 %d 的节点不存在\n", newHeroNode.num);
}
}
/**
* 根据 num 删除节点
* @param heroNode
*/
public void delete(HeroNode heroNode){
if (head.next == null){
System.out.println("链表为空");
}
HeroNode temp = head;
boolean flag = false;
while (true){
if (temp.next == null){
break;
}
if (temp.next.num == heroNode.num){
flag = true;
break;
}
temp = temp.next;
}
if (flag){
temp.next = temp.next.next;
}else {
System.out.printf("要删除的排位 %d 的节点不存在", heroNode.num);
}
}
/**
* 显示链表
*/
public void list(){
if (head.next == null){
System.out.println("链表为空");
}
HeroNode temp = head.next;
while (true){
if (temp == null){
break;
}
System.out.println(temp);
temp = temp.next;
}
}
}
class HeroNode {
public String name;
public Integer num;
public HeroNode next; //指向下一个节点
//构造器
public HeroNode(String name){
this.name = name;
}
public HeroNode(Integer num, String name){
this.num = num;
this.name = name;
};
@Override
public String toString() {
return "HeroNode{" +
"name='" + name + '\'' +
", num=" + num +
'}';
}
}