标签：str logs blog lin log style color node get
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.
可以分为递归解法和非递归解法。
递归解法：
/** * 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) { if (!l1) return l2; if (!l2) return l1; if (l1->val < l2->val) { l1->next = mergeTwoLists(l1->next, l2); return l1; } else { l2->next = mergeTwoLists(l1, l2->next); return l2; } } };
非递归解法：
class Solution { public: ListNode* mergeTwoLists(ListNode* l1, ListNode* l2) { ListNode *dummy = new ListNode(-1), *cur = dummy; while (l1 && l2) { if (l1->val < l2->val) { cur->next = l1; l1 = l1->next; } else { cur->next = l2; l2 = l2->next; } cur = cur->next; } cur->next = l1 ? l1 : l2; return dummy->next; } };
Leetcode 21. Merge Two Sorted Lists
标签：str logs blog lin log style color node get
原文地址：http://www.cnblogs.com/yuanluo/p/6876140.html
