摘要：
Given a linked list, determine if it has a cycle in it. Example Given -21->10->4->5, tail connects to node index 1, return true Given -21->10->4->5, t 阅读全文
摘要：
Given a digit string, return all possible letter combinations that the number could represent. A mapping of digit to letters (just like on the telepho 阅读全文
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Given a list of non negative integers, arrange them such that they form the largest number. Given [1, 20, 23, 4, 8], the largest formed number is 8423 阅读全文
摘要：
Find the kth smallest number in at row and column sorted matrix. Given k = 4 and a matrix: [ [1 ,5 ,7], [3 ,7 ,8], [4 ,8 ,9], ] return 5 public class 阅读全文