420. 强密码检验器 一个强密码应满足以下所有条件: 由至少6个,至多20个字符组成. 至少包含一个小写字母,一个大写字母,和一个数字. 同一字符不能连续出现三次 (比如 "-aaa-" 是不允许的, 但是 "-aa-a-" 是可以的). 编写函数 strongPasswordChecker(s),s 代表输入字符串,如果 s 已经符合强密码条件,则返回0:否则返回要将 s 修改为满足强密码条件的字符串所需要进行修改的最小步数. 插入.删除.替换任一字符都算作一次…

A password is considered strong if below conditions are all met: It has at least 6 characters and at most 20 characters. It must contain at least one lowercase letter, at least one uppercase letter, and at least one digit. It must NOT contain three r…

原创:扣钉日记(微信公众号ID:codelogs),欢迎分享,转载请保留出处. 简介 前面在密码学入门一文中讲解了各种常见的密码学概念.算法与运用场景,但没有介绍过代码,因此,为作补充,这一篇将会介绍使用Java语言如何实现使用这些算法,并介绍一下使用过程中可能遇到的坑. Java加密体系JCA Java抽象了一套密码算法框架JCA(Java Cryptography Architecture),在此框架中定义了一套接口与类,以规范Java平台密码算法的实现,而Sun,SunRsaSign,Su…

Find all possible combinations of k numbers that add up to a number n, given that only numbers from 1 to 9 can be used and each combination should be a unique set of numbers. Ensure that numbers within the set are sorted in ascending order. Example 1…

Given a string S, you are allowed to convert it to a palindrome by adding characters in front of it. Find and return the shortest palindrome you can find by performing this transformation. For example: Given "aacecaaa", return "aaacecaaa&qu…

Given a 2D board and a list of words from the dictionary, find all words in the board. Each word must be constructed from letters of sequentially adjacent cell, where "adjacent" cells are those horizontally or vertically neighboring. The same le…

Design a data structure that supports the following two operations: void addWord(word)bool search(word) search(word) can search a literal word or a regular expression string containing only letters a-z or .. A . means it can represent any one letter.…

There are a total of n courses you have to take, labeled from 0 to n - 1. Some courses may have prerequisites, for example to take course 0 you have to first take course 1, which is expressed as a pair: [0,1] Given the total number of courses and a l…

前两天运维反馈说,有些机器的max_allowed_packet隔两天就会被改成1024,导致客户端调用时出错,网上有说内存不够的,也有人工修改的. 运维小姑娘一口咬定肯定没有改过的,而且my.cnf中包含了. 昨天下班前开了general_log,早上过来grep "SET" | grep -A10 -b10 "packet"一遍,果然被攻击后修改了. 要求强密码策略. 主要是mysql没有设置密码策略,以及连续n次登录错误后没有自动锁定账号导致,截止最新5.7.…

Given a 2d grid map of '1's (land) and '0's (water), count the number of islands. An island is surrounded by water and is formed by connecting adjacent lands horizontally or vertically. You may assume all four edges of the grid are all surrounded by…