实现链表的插入——头插尾插

public class LinkList {
    LinkList next;
    int val;
    public LinkList(int val) {
        this.val = val;
    }
    public LinkList getNext() {
        return next;
    }
    public void setNext(LinkList next) {
        this.next = next;
    }
    public int getVal() {
        return val;
    }
    public void setVal(int val) {
        this.val = val;
    }
}

public static void insert1(int val) {
        LinkList node = new LinkList(val);
        //判断是否为空
        if (head == null) {
            head = node;
            return;
        }
        node.next = head;
        head = node;
    }

 public static void insert2(int val) {
        LinkList node = new LinkList(val);
        //判断是否为空
        if (head == null) {
            head = node;
            return;
        }
        LinkList temp = head;
        //遍历到最后插入
        while (temp.next != null) {
            temp = temp.next;
        }
        temp.next = node;
    }

public static void main(String[] args) {
        insert1(3);
        insert2(4);
        insert1(2);
        insert2(5);
        insert1(1);
        insert2(6);
        bianli();
    }
//遍历
    public static void bianli() {
        LinkList temp = head;
        while (temp != null) {
            System.out.println(temp.val + " ");
            temp = temp.next;
        }
    }