04.双向链表

/**
 * 双向链表
 */
public class DoubleLinkListDemo {
    public static void main(String[] args){
        DoubleLinkList linkList = new DoubleLinkList();
        DoubleNode n1 = new DoubleNode(1,"A");
        DoubleNode n2 = new DoubleNode(2,"B");
        DoubleNode n3 = new DoubleNode(3,"C");
        DoubleNode n4 = new DoubleNode(4,"D");
        linkList.add(n1);
        linkList.add(n2);
        System.out.println("add----");
        linkList.list();
        DoubleNode n11 = new DoubleNode(1,"A~");
        linkList.update(n11);
        System.out.println("update----");
        linkList.list();
        linkList.del(1);
        System.out.println("del----");
        linkList.list();
        System.out.println("-------------");
        DoubleLinkList linkList2 = new DoubleLinkList();
        DoubleNode n12 = new DoubleNode(1,"A");
        DoubleNode n22 = new DoubleNode(2,"B");
        DoubleNode n32 = new DoubleNode(3,"C");
        DoubleNode n42 = new DoubleNode(4,"D");
        linkList2.addOrder(n22);
        linkList2.addOrder(n32);
        linkList2.addOrder(n12);
        linkList2.addOrder(n42);
        System.out.println("add----");
        linkList2.list();
        DoubleNode n111 = new DoubleNode(1,"A~");
        linkList2.update(n111);
        System.out.println("update----");
        linkList2.list();
        linkList2.del(1);
        System.out.println("del----");
        linkList2.list();
    }
    //add----
    //DoubleNode{no=1, data='A', next=2, pre=0}
    //DoubleNode{no=2, data='B', next=null, pre=1}
    //update----
    //DoubleNode{no=1, data='A~', next=2, pre=0}
    //DoubleNode{no=2, data='B', next=null, pre=1}
    //del----
    //DoubleNode{no=2, data='B', next=null, pre=0}
    //-------------
    //add----
    //DoubleNode{no=1, data='A', next=2, pre=0}
    //DoubleNode{no=2, data='B', next=3, pre=1}
    //DoubleNode{no=3, data='C', next=4, pre=2}
    //DoubleNode{no=4, data='D', next=null, pre=3}
    //update----
    //DoubleNode{no=1, data='A~', next=2, pre=0}
    //DoubleNode{no=2, data='B', next=3, pre=1}
    //DoubleNode{no=3, data='C', next=4, pre=2}
    //DoubleNode{no=4, data='D', next=null, pre=3}
    //del----
    //DoubleNode{no=2, data='B', next=3, pre=0}
    //DoubleNode{no=3, data='C', next=4, pre=2}
    //DoubleNode{no=4, data='D', next=null, pre=3}
}
class DoubleLinkList{
    //头结点
    private DoubleNode head = new DoubleNode(0,"");

    public DoubleNode getHead() {
        return head;
    }

    private boolean addMethod = false;
    //顺序插入
    public void add(DoubleNode node){
        this.addMethod = true;
        DoubleNode temp = head;
        //找尾结点
        while (true){
            if (temp.next==null){
                break;
            }
            temp = temp.next;
        }
        temp.next = node;
        node.pre = temp;
    }
    //有序插入 根据no
    public void addOrder(DoubleNode node){
        if (addMethod){
            System.out.println("有序插入不能与add()调用后使用!");
            return;
        }
        DoubleNode temp = head;
        boolean flag = false; //重复的no
        while (true){
            if (temp.next==null){
                break;
            }else if (temp.next.no == node.no){
                flag = true;
                System.out.println("存在重复的Node");
                break;
            }else if (temp.next.no > node.no){
                break;
            }
            temp = temp.next;
        }
        if (!flag){
            node.next = temp.next;
            temp.next = node;
            temp.next.pre = temp;
            if (node.next!=null){
                node.next.pre = node;
            }
        }
    }
    //修改 根据no 修改data
    public void update(DoubleNode node){
        if (head.next==null){
            System.out.println("链表为空");
            return;
        }
        DoubleNode temp = head.next;
        boolean flag  = false; //是否存在该节点
        while (true){
            if (temp == null){
                break;
            }
            if (temp.no == node.no){
                flag = true;
                break;
            }
            temp = temp.next;
        }
        if (flag){
            temp.data = node.data;
        }else {
            System.out.println("不存在该结点,不能修改");
        }
    }
    //根据no删除结点
    public void del(int no){
        if (head.next==null){
            System.out.println("链表为空");
            return;
        }
        DoubleNode temp = head.next;
        boolean flag  = false; //是否存在该结点
        while (true){
            if (temp == null){
                break;
            }
            if (temp.no == no){
                flag = true;
                break;
            }
            temp = temp.next;
        }
        if (flag){
            temp.pre.next = temp.next;
            if (temp.next!=null){
                temp.next.pre = temp.pre;
            }
        }else {
            System.out.println("不存在该结点,不能删除");
        }
    }
    //显示单链表
    public void list(){
        if (head.next==null){
            System.out.println("链表为空");
            return;
        }
        DoubleNode temp = head.next;
        while (true){
            if (temp!=null){
                System.out.println(temp);
                temp = temp.next;
            }else {
                break;
            }
        }
    }
}
class DoubleNode{
    public int no;
    public String data;
    public DoubleNode next;
    public DoubleNode pre;

    public DoubleNode(int no, String data) {
        this.no = no;
        this.data = data;
    }

    @Override
    public String toString() {
        if (next!=null){
            return "DoubleNode{" +
                    "no=" + no +
                    ", data='" + data + '\'' +
                    ", next=" + next.no +
                    ", pre=" + pre.no +
                    '}';
        }else {
            return "DoubleNode{" +
                    "no=" + no +
                    ", data='" + data + '\'' +
                    ", next=null"  +
                    ", pre=" + pre.no +
                    '}';
        }
    }
}