Java-合并链表（递归）

合并链表，递归比较链表的头，哪个小就next哪个

/*
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;
        if(list2==null) return list1;
        ListNode Merge_=null;
        if(list1.val<list2.val){
            Merge_=list1;
            Merge_.next=Merge(list1.next,list2);
        }else{
            Merge_=list2;
            Merge_.next=Merge(list1,list2.next);         
        }
        return Merge_;

    }
}