摘要： 定义栈的数据结构，请在该类型中实现一个能够得到栈中所含最小元素的min函数（时间复杂度应为O（1））。 分析：1、对于抽象问题，可以尝试用举例法理解题目 2、栈：先进后出 入栈和出栈的时间复杂度都是1。 但是查找最小值就有点麻烦。加入我用变量存栈的最小值那么就有一个问题。如果最小值被弹出怎么办？所以 阅读全文

摘要： Given an array with n objects colored red, white or blue, sort them in-place so that objects of the same color are adjacent, with the colors in the or 阅读全文

摘要： 转处：https://www.cnblogs.com/gw811/archive/2012/10/04/2711746.html 阅读全文

摘要： Find the kth largest element in an unsorted array. Note that it is the kth largest element in the sorted order, not the kth distinct element. Example 阅读全文

摘要： Given a string and a string dictionary, find the longest string in the dictionary that can be formed by deleting some characters of the given string. 阅读全文

摘要： HashMap和HashSet的区别是Java面试中最常被问到的问题。如果没有涉及到Collection框架以及多线程的面试，可以说是不完整。而Collection框架的问题不涉及到HashSet和HashMap，也可以说是不完整。HashMap和HashSet都是collection框架的一部分， 阅读全文

摘要： Given a linked list, determine if it has a cycle in it. To represent a cycle in the given linked list, we use an integer pos which represents the posi 阅读全文

摘要： Given two sorted integer arrays nums1 and nums2, merge nums2 into nums1 as one sorted array. Note: The number of elements initialized in nums1 and num 阅读全文

摘要： Write a function that takes a string as input and reverse only the vowels of a string. Example 1: Example 2: Input: "leetcode" Output: "leotcede" Exam 阅读全文

摘要： 题目： Given a non-negative integer c, your task is to decide whether there're two integers a and b such that a2 + b2 = c. Example 1: Example 2: 方法二：数学方法 阅读全文