摘要： 题目： You are given two linked lists representing two non-negative numbers. The digits are stored in reverse order and each of their nodes contain a sin 阅读全文

摘要： 题目： 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 阅读全文

摘要： 题目：Given an array S of n integers, find three integers in S such that the sum is closest to a given number, target. Return the sum of the three intege 阅读全文