[LeetCode] Merge Two Sorted Lists

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.

解题思路：

这道题是我做的leetcode最容易的题目了。其中有个小技巧，就是在最开始的时候申请一个头结点，然后在融合之后再删除头结点。这样能够让代码更加清晰。利用原有的空间，更加加快了效率，，在leetcode跑的时间仅仅13ms。Talk is cheap, show you the cade:

/** * Definition for singly-linked list. * struct ListNode { *int val; *ListNode *next; *ListNode(int x) : val(x), next(NULL) {} * }; */class Solution {public:ListNode *mergeTwoLists(ListNode *l1, ListNode *l2) {ListNode* head=new ListNode(0);ListNode* p = head;//指向融合的最后一个元素while(l1!=NULL&&l2!=NULL){if(l1->val<l2->val){p->next=l1;p=l1;l1=l1->next;}else{p->next=l2;p=l2;l2=l2->next;}}while(l1!=NULL){p->next=l1;p=l1;l1=l1->next;}while(l2!=NULL){p->next=l2;p=l2;l2=l2->next;}p->next = NULL;p=head;head=head->next;delete p;return head;}};

志在山顶的人，不会贪念山腰的风景。