将两个排序链表合并为一个新的排序链表
样例
给出 1->3->8->11->15->null
,2->null
,
返回 1->2->3->8->11->15->null
。
* Definition for ListNode.
* public class ListNode {
* int val;
* ListNode next;
* ListNode(int val) {
* this.val = val;
* this.next = null;
* }
* }
*/
public class Solution {
/**
* @param ListNode l1 is the head of the linked list
* @param ListNode l2 is the head of the linked list
* @return: ListNode head of linked list
*/
public ListNode mergeTwoLists(ListNode l1, ListNode l2) {
// write your code here
if(l1==null)
return l2;
if(l2==null)
return l1;
ListNode res = new ListNode(0);
ListNode temp = res;
while(l1!=null && l2!=null){
if(l1.val<=l2.val){
temp.next=new ListNode(l1.val);
l1=l1.next;
temp = temp.next;
}else{
temp.next=new ListNode(l2.val);
l2=l2.next;
temp = temp.next;
}
if(l1!=null){
temp.next=l1;
}
if(l2!=null){
temp.next=l2;
}
return res.next;
}
}