摘要：题目大意：深拷贝一个链表，链表除了含有next指针外，还包含一个random指针，该指针指向字符串中的某个节点或者为空。 节点定义为： struct RandomListNode { int label; RandomListNode *next, *random; RandomListNode(i 阅读全文

摘要：Implement a basic calculator to evaluate a simple expression string. The expression string may contain open ( and closing parentheses ), the plus + or 阅读全文

摘要：Given an array S of n integers, are there elements a, b, c, and d in S such that a + b + c + d = target? Find all unique quadruplets in the array whic 阅读全文

摘要：2017-10-04 16:30:13 Given an array S of n integers, are there elements a, b, c in S such that a + b + c = 0? Find all unique triplets in the array whi 阅读全文

摘要：Given an array of integers, return indices of the two numbers such that they add up to a specific target. You may assume that each input would have ex 阅读全文