【　課題　】class Node{
int key;
Node next;}
class LinkedListByObject{
static Node head, z, t;
static void listInitialize(){
head = new Node();
z = new Node();
head.next = z;
z.next = z;}
static void deleteNext(Node t){
//★課題1-1}
static Node insertAfter(int v, Node t){
Node x;
x = new Node();
x.key = v; x.next = t.next;
t.next = x;
return x;}