摘要：
题意 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 w 阅读全文
摘要：
题意 Given a digit string, return all possible letter combinations that the number could represent. A mapping of digit to letters (just like on the tele 阅读全文
摘要：
题意 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
摘要：
题意 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 which gives the sum 阅读全文