Java implements a linked list

Java implements a linked list

Public class MyList {static class Node {// Node class Object data; Node next; public Node (Object data) {// constructor, assign this to data. data = data; this. next = null ;}} Node head; public MyList () {head = null; // constructor} public void clear () {// clear linked list head = null ;} public void bianli () // traverse {Node p = head; while (p! = Null) {System. out. print (p. data + ""); p = p. next;} System. out. println ();} public boolean isEmpty () // judge whether it is null {return head = null;} public int size () {// number of nodes Node p = head; int sum = 0; while (p! = Null) {sum ++; p = p. next;} return sum;} // insert an element at the specified position. The subscript starts from 0 and public void insert (Object d, int pos) {if (pos <0 | pos> size () {throw new RuntimeException ("subscript error");} Node newNode = new Node (d ); if (pos = 0) {newNode. next = head; head = newNode;} else if (pos> = size ()-1) {get (size ()-1 ). next = newNode;} else {newNode. next = get (pos); get (pos-1 ). next = newNode;} public Node get (int pos) {if (pos <0 | pos> size () {throw new RuntimeException ("subscript error ");} if (pos = 0) return head; Node p = head; for (int I = 0; I <pos; I ++) p = p. next; return p;} public static void main (String [] args) {MyList list = new MyList (); list. insert (10, 0); list. insert (20, 1); list. insert (30, 0); list. insert (40, 1); System. out. println (list. size (); list. bianli (); System. out. println (list. isEmpty (); System. out. println (list. get (2 ). data); list. clear (); System. out. println (list. isEmpty ());}}