多校10 1002 HDU 6172 Array Challenge 题意 There's an array that is generated by following rule. \(h_0=2,h_1=3,h_2=6,h_n=4h_{n-1}+17h_{n-2}-12h_{n-3}-16\) And let us define two arrays bnandan as below. $ b_n=3h_{n+1} h_n+9h_{n+1} h_{n-1}+9h_n^2+27h_n h_{n…
Factorization or factoring consists of writing a number or another mathematical object as a product of several factors, usually smaller or simpler objects of the same kind. For example, 3 × 5 is a factorization of the integer 15, and (x – 2)(x + 2) i…
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…