雙向連結串列的實際應用：

package com.model.linkedlist.doubly;

/**
 * @Description:測試類
 * @Author: 張紫韓
 * @Crete 2021/7/9 9:57
 * 雙向連結串列的介紹
 */
public class DoublyLinkedListDemo01 {
    public static void main(String[] args) {
        DoublyLinkedList list=new DoublyLinkedList();
        list.add(
 
new Node(1,"a"));
        list.add(new Node(2,"a"));
        list.add(new Node(3,"a"));
        list.add(new Node(4,"a"));
        list.add(new Node(5,"a"));
        list.show();
        list.delete(new Node(1,"a"));
        list.show();
        list.update(new Node(2,"張紫韓"));
        list.show();
        DoublyLinkedList list1 
 
= new DoublyLinkedList();
        list1.addInOrder(new Node(3,"a"));
        list1.addInOrder(new Node(2,"a"));
        list1.addInOrder(new Node(1,"a"));
        list1.addInOrder(new Node(4,"a"));
        System.out.println("按順序新增節點");
        list1.show();
    }
}
//雙向連結串列類
class DoublyLinkedList{
    
 
private Node head=new Node();
    public Node getHead() {
        return head;
    }
    //新增元素,到連結串列的最後端
    public void add(Node node){
        Node temp=head;
        while(true){
            if (temp.next==null){
                break;
            }
            temp=temp.next;
        }
        temp.next=node;
        node.pre=temp;
    }
//    按這id號的大小進行新增
    public void addInOrder(Node node){
        Node temp=head;
        boolean flag=false;//是否可以進行新增
        while(true){
            if (temp.next==null){
                break;
            }
            if (temp.next.id>node.id){
                break;
            }
            if (temp.next.id==node.id){
                flag=false;
                break;
            }
            temp=temp.next;
        }
        if (flag){
            System.out.println("已經存在此節點，不能進行重複的新增");

        }else {
            //判斷是加在連結串列的最後還是連結串列的中間部分
            if (temp.next==null) {
                temp.next = node;
                node.pre = temp;
            }else {
                node.next = temp.next;
                node.pre = temp;
                temp.next = node;
                node.next.pre = node;
            }
        }
    }
    //刪除元素
    public void delete(Node node){
        if (isEmpty()){
            System.out.println("連結串列為空不能進行刪除");
            return;
        }
        Node temp=head.next;
        boolean flag=false;
        while (true){
            if (temp==null){
                break;
            }
            if (temp.id==node.id){
                flag=true;
                break;
            }
            temp=temp.next;
        }
        if (flag){
            temp.pre.next=temp.next;
            temp.next.pre=temp.pre;
        }else {
            System.out.println("沒有找到此節點不能進行刪除");
        }

    }
//    修改節點
    public void update(Node node){
        if (isEmpty()){
            System.out.println("連結串列為空，不能進行修改");
            return;
        }
        Node temp=head.next;
        boolean flag=false;
        while (true){
            if (temp==null){
                break;
            }
            if (temp.id==node.id){
                flag=true;
                break;
            }
            temp=temp.next;
        }
        if (flag){
            temp.name=node.name;
        }else {
            System.out.println("沒有找到此節點，不能進行修改");
        }
    }

//    遍歷連結串列
    public void show(){
        Node temp=head.next;
        while(true){
            if (temp==null){
                break;
            }
            System.out.println(temp.toString());
            temp=temp.next;
        }
    }

    public boolean isEmpty(){
        if (head.next==null){
            return true;
        }
        return false;
    }

}
//雙向連結串列的節點類
class Node{
    public int id;
    public String name;
    public Node pre;
    public Node next;

    public Node() {
    }

    @Override
    public String toString() {
        return "Node{" +
                "id=" + id +
                ", name='" + name + '\'' +
                '}';
    }

    public Node(int id, String name) {
        this.id = id;
        this.name = name;
    }
}