摘要：
Given an integer n, return 1 - n in lexicographical order. For example, given 13, return: [1,10,11,12,13,2,3,4,5,6,7,8,9]. Please optimize your algori 阅读全文
摘要：
Given a linked list, swap every two adjacent nodes and return its head. Example: Note: Your algorithm should use only constant extra space. You may no 阅读全文
摘要：
Reverse a singly linked list. Example: Follow up: A linked list can be reversed either iteratively or recursively. Could you implement both? 反转链表，链表算法 阅读全文
摘要：
Given a linked list, reverse the nodes of a linked list k at a time and return its modified list. k is a positive integer and is less than or equal to 阅读全文