合并两个有序链表 

 1 /*
 2 struct ListNode {
 3     int val;
 4     struct ListNode *next;
 5     ListNode(int x) :
 6             val(x), next(NULL) {
 7     }
 8 };*/
 9 class Solution {
10 public:
11     ListNode* Merge(ListNode* pHead1, ListNode* pHead2)
12     {
13         ListNode* newhead = new ListNode(-1);
14         ListNode* temp = newhead;
15         if(!pHead1) return pHead2;
16         if(!pHead2) return pHead1;
17         while(pHead1 && pHead2){
18             if(pHead1->val <=pHead2->val){
19                 temp->next = pHead1;
20                 pHead1 = pHead1->next;
21                 temp = temp->next;
22             }
23             else{
24                 temp->next = pHead2;
25                 pHead2 = pHead2->next;
26                 temp = temp->next;
27             }
28         }
29         if(!pHead1){
30             temp->next = pHead2;
31         }
32         if(!pHead2){
33             temp->next = pHead1;
34         }
35         return newhead->next;
36     }
37 };
 1 /*
 2 struct ListNode {
 3     int val;
 4     struct ListNode *next;
 5     ListNode(int x) :
 6             val(x), next(NULL) {
 7     }
 8 };*/
 9 class Solution {
10 public:
11     ListNode* Merge(ListNode* pHead1, ListNode* pHead2)
12     {
13         ListNode* head;
14         if(!pHead1) return pHead2;
15         if(!pHead2) return pHead1;
16         if(pHead1->val <= pHead2->val){
17             head=pHead1;
18             head->next = Merge(pHead1->next,pHead2);
19         }
20         else{
21             head = pHead2;
22             head->next = Merge(pHead1,pHead2->next);
23         }
24         return head;
25     }
26 };

 

posted @ 2019-07-05 17:39  Austin_anheqiao  阅读(140)  评论(0)    收藏  举报