#-*- coding: UTF-8 -*- # Definition for singly-linked list.# class ListNode(object):#     def __init__(self, x):#         self.val = x#         self.next = Noneclass Solution(object):    def swapPairs(self, head):        """        :type he…

Swap Nodes in Pairs Given a linked list, swap every two adjacent nodes and return its head. For example,Given 1->2->3->4, you should return the list as 2->1->4->3. Your algorithm should use only constant space. You may not modify the val…

一天一道LeetCode系列 (一)题目 Given a linked list, swap every two adjacent nodes and return its head. For example, Given 1->2->3->4, you should return the list as 2->1->4->3. Your algorithm should use only constant space. You may not modify the v…

Given a linked list, swap every two adjacent nodes and return its head. For example,Given 1->2->3->4, you should return the list as 2->1->4->3. Your algorithm should use only constant space. You may not modify the values in the list, onl…

因为不太熟悉链表操作,所以解决方法烦了点,空间时间多有冗余. 代码中l,r分别是每一组的需要交换的左右指针,temp是下一组的头指针,用于交换后链接:res是交换后的l指针,用于本组交换后尾指针在下一组交换后链接上交换后的头指针. /** * Definition for singly-linked list. * struct ListNode { * int val; * ListNode *next; * ListNode(int x) : val(x), next(NULL) {} *…

# -*- coding: utf8 -*-'''__author__ = 'dabay.wang@gmail.com' 24: Swap Nodes in Pairshttps://oj.leetcode.com/problems/swap-nodes-in-pairs/ Given a linked list, swap every two adjacent nodes and return its head. For example,Given 1->2->3->4, you sh…

24. Swap Nodes in Pairs Given a linked list, swap every two adjacent nodes and return its head. For example,Given 1->2->3->4, you should return the list as 2->1->4->3. Your algorithm should use only constant space. You may not modify the…

24. Swap Nodes in Pairs Given a linked list, swap every two adjacent nodes and return its head. For example, Given ->->->, you should ->->->. Your algorithm should use only constant space. You may not modify the values in the list, only…

24. Swap Nodes in Pairs Given a linked list, swap every two adjacent nodes and return its head. For example,Given 1->2->3->4, you should return the list as 2->1->4->3. Your algorithm should use only constant space. You may not modify the…

Swap Nodes in Pairs  Given a linked list, swap every two adjacent nodes and return its head. For example, Given 1->2->3->4, you should return the list as 2->1->4->3. Your algorithm should use only constant space. You may not modify the v…