LeetCode(21)题解:Merge Two Sorted Lists

https://leetcode.com/problems/merge-two-sorted-lists/

Merge two sorted linked lists and return it as a new list. The new list should be made by splicing together the nodes of the first two lists.

思路：

考察链表操作，没啥说的。

AC代码：

 1 /**

 2  * Definition for singly-linked list.

 3  * struct ListNode {

 4  *     int val;

 5  *     ListNode *next;

 6  *     ListNode(int x) : val(x), next(NULL) {}

 7  * };

 8  */

 9 class Solution {

10 public:

11     ListNode* mergeTwoLists(ListNode* l1, ListNode* l2) {

12         ListNode *p=new ListNode(0);

13         ListNode *q=p;

14         while(l1!=NULL && l2!=NULL){

15             if(l1->val<l2->val){

16                 q->next=l1;

17                 q=q->next;

18                 l1=l1->next;

19             }

20             else{

21                 q->next=l2;

22                 q=q->next;

23                 l2=l2->next;

24             }

25         }

26             if(l1!=NULL)

27                 q->next=l1;

28             else

29                 q->next=l2;

30             p=p->next;

31             return p;

32     }

33 };