// --- Directions // Write a function that returns the number of vowels // used in a string. Vowels are the characters 'a', 'e' // 'i', 'o', and 'u'. // --- Examples // vowels('Hi There!') --> 3 // vowels('Why do you ask?') --> 4 // vowels('Why?') -…
这篇BLOG是我很早以前写的,因为现在搬移到CNBLOGS了,经过整理后重新发出来. 工作之前的几年一直都在搞计算机安全/病毒相关的东西(纯学习,不作恶),其中PE文件格式是必须知识.有些PE文件,比如驱动,系统会在加载时对checksum进行校验,确保驱动文件的完整性.关于PE文件如何校验,网上有很多资料可以学习,这里有一篇文章<An Analysis of the Windows PE Checksum Algorithm>是对WINDOWS API CheckSumMappedFile…
Sept. 10, 2015 Study again the back tracking algorithm using recursive solution, rat in maze, a classical problem. Made a few of mistakes through the practice, one is how to use two dimension array, another one is that "not all return path returns va…
Write a function that takes a string as input and reverse only the vowels of a string. Example 1:Given s = "hello", return "holle". Example 2:Given s = "leetcode", return "leotcede". 这道题让我们翻转字符串中的元音字母,元音字母有五个a,e,i,o…
