/**
* 题目：合并两个排序的链表
* 描述：输入两个单调递增的链表，输出两个链表合成后的链表，当然我们需要合成后的链表满足单调不减规则。
* 解决方案：
* */
public class Four {//递归public static ListNode one(ListNode listOne,ListNode listTwo) { if(listOne == null ) {return listTwo;}if(listTwo == null ) {return listOne;}ListNode head = null;if(listOne.var <listTwo.var) {head = listOne;head.next =one(listOne.next,listTwo);}else {head = listTwo;head.next = one(listOne,listTwo.next);} return head;}//非递归public static ListNode two(ListNode listOne,ListNode listTwo) { if(listOne == null ) {return null;}if(listTwo == null ) {return null;}ListNode temp = null;if(listOne.var < listTwo.var ) {temp =listOne;listOne = listOne.next;//将当前节点的后一个节点赋值给listOne}else {temp =listOne;listOne = listOne.next;}while(listOne!=null && listTwo != null) {if(listOne.var < listTwo.var) {temp.next = listOne;listOne = listOne.next;}else {temp.next = listTwo;listTwo = listTwo.next;}}return temp;}class ListNode{int var;ListNode next;}}