剑指offer题解 合并两个排序的链表

/*
public class ListNode {
int val;
ListNode next = null;

ListNode(int val) {
this.val = val;
}
}*/
public class Solution {
public ListNode Merge(ListNode  list1,ListNode list2) {
if(list1==null) return list2;
else if(null==list2) return list1;
ListNode head=null;
if(list1.val>list2.val){
head=list2;
head.next=Merge(list1,list2.next);
}else{
head=list1;
head.next=Merge(list1.next,list2);
}
return head;
}
}