数据结构------链表

public class Node {
     int data;

     Node next;

    public Node(int data) {
        next = null;
        this.data = data;
    }

    public int getData() {
        return data;
    }

    public void setData(int data) {
        this.data = data;
    }

    public Node getNext() {
        return next;
    }

    public void setNext(Node next) {
        this.next = next;
    }
}



















/**
 * @time 单向链表
 */
public class LinkdList02 {

    private Node head;  //头节点
    private int length;   //长度

    public int getLength() {
        return length;
    }

    public LinkdList02() {
        head = new Node(0);
        length = 0;
    }


    /**
     * 插入
     * @param index
     * @param data
     * @return
     */
    public boolean insert(int index, int data){

        if (index > length || index < 0)
            return false;

        Node curNode = head;
        Node newNode = new Node(data);
        Node parent = null;
        int flag = 0;
        while (curNode.next != null){
            if (flag < index){
                flag++;
                parent = curNode;
                curNode = curNode.next;
            }else {
                newNode.next = curNode;
                parent.next = newNode;
                return true;
            }
        }
        return false;
    }

    /**
     * 删除
     * @param data
     * @return
     */
    public boolean delete(int data){
        Node curNode = head;
        Node parent = null;
        while (curNode.next != null){
            parent = curNode;
            curNode = curNode.next;
            if (curNode.data == data){
                parent.next = curNode.next;
                return true;
            }
        }
        return false;
    }

    /**
     * 查找
     * @param data
     * @return
     */
    public boolean search(int data){
        Node curNode = head;
        while (curNode.next != null){
            curNode = curNode.next;
            if (curNode.data == data)
                return true;
        }
        return false;
    }


    /**
     * 插入
     * @param data
     * @return
     */
    public boolean insert(int data){
        Node newNode = new Node(data);
        Node curNode = head;

        while (curNode.next != null){
            curNode = curNode.next;
        }
        length++;
        curNode.next = newNode;
        return false;
    }

    /**
     * 输出
     */
    public void print(){
        Node curNode = head;
        while (curNode.next != null){
            curNode = curNode.next;
            System.out.println(curNode.data);
        }
    }

    /**
     * 判断是否存在链表
     * @return
     */
    public boolean isEmpty(){
        if (head.next == null)
            return true;
        return false;
    }


    public static void main(String[] args) {
        LinkdList02 list02 = new LinkdList02();
        list02.insert(1);
        list02.insert(2);
        list02.insert(3);
        list02.insert(4);

        list02.delete(4);
        list02.insert(2,5);
        list02.print();
        if (list02.isEmpty())
            System.out.println("该链表不存在" + list02.getLength());
        else
            System.out.println("该链表存在" + list02.getLength());
    }
}