标签：const odi tno style ret next use lis values
Given a linked list, swap every two adjacent nodes and return its head.
Example:
Given 1->2->3->4, you should return the list as 2->1->4->3.
Note:
class Solution{ public: ListNode* swapPairs(ListNode* head){ ListNode *dummy = new ListNode(-1); ListNode *pre = dummy; dummy->next = head; while(pre->next && pre->next->next){ ListNode *t = pre->next->next; pre->next->next = t->next; t->next = pre->next; pre->next = t; pre = t->next; } return dummy->next; } }; //递归写法稍微有些复杂 class Solution{ public: ListNode* swapPairs(ListNode* head){ if(!head || !head->next) return head; ListNode *t = head->next; head->next = swapPairs(head->next->next); t->next = head; return t; } };
标签：const odi tno style ret next use lis values
原文地址：https://www.cnblogs.com/hujianglang/p/11415658.html
