为了避免浮点运算,不妨将$f_{i}$​​​乘上$C=10^{2}$​​​,问题即求$\max_{S\subseteq [1,n]}\frac{\sum_{i\in S}(C^{2}-(\sum_{j\in S}f_{j}-f_{i})f_{i})s_{i}}{C^{2}}$​​​ 记$F=\sum_{i\in S}f_{i}$​​,考虑枚举$F$​​,并以$f_{i}$​​为质量.$(C^{2}-(F-f_{i})f_{i})s_{i}$​​为价值,问题即是要求质量和恰为$F$​​的最大价值和…

作者:zhbzz2007 出处:http://www.cnblogs.com/zhbzz2007 欢迎转载,也请保留这段声明.谢谢! 1 模块简介 Python 3.5 增加了一个有意思的库--typing.这将会给Python增加了类型暗示.类型暗示是一种可以将你的函数变量声明为一种特定类型的声明.当然,类型暗示并不是绑定.它仅仅是暗示,所以这种机制并不能阻止工程师传入他们不应该传入的参数.这个就是Python.你可以在PEP 484中阅读类型暗示的说明,或者你也可以在PEP 483 阅读背后…

最新在做公司的一个项目,需要实现一个敲打代码的动画效果,粗意味比较简单,果断自己直接开写,写着写着发现是一个坑.需要支持语法高亮,并不能直接简单的用setTimeout来动态附件innerHTML.苦思猛想数小时后,果断用动态生成DOM的方法实现了整个效果. typing.js的打印效果甚至能够支持表格.按钮.表单,只要你页面能够呈现出来的,都可以以一种动态输出的感觉打印出来! 强烈推荐观看完整DEMO 我在网上查了一下,应该目前是没有一个插件是和typing.js效果一致的! 浏览器兼容性方面…

Monkey Patch Monkey Testing Duck Typing Duck Test…

    Programming Contest Problem Types Hal Burch conducted an analysis over spring break of 1999 and made an amazing discovery: there are only 16 types of programming contest problems! Furthermore, the top several comprise almost 80% of the problems s…

Area of Mushroom Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others)Total Submission(s): 2390    Accepted Submission(s): 578 Problem Description Teacher Mai has a kingdom with the infinite area. He has n students guard…

Differencia Time Limit: 10000/10000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others)Total Submission(s): 601    Accepted Submission(s): 173 Problem Description Professor Zhang has two sequences a1,a2,...,an and b1,b2,...,bn. He wants to…

Rigid Frameworks Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others)Total Submission(s): 337    Accepted Submission(s): 273 Problem Description Erik Demaine is a Professor in Computer Science at the Massachusetts Insti…

题目链接: Coding Contest Time Limit: 2000/1000 MS (Java/Others)     Memory Limit: 65536/65536 K (Java/Others) Problem Description A coding contest will be held in this university, in a huge playground. The whole playground would be divided into N blocks,…

偏方记录背包里的物品.....每个背包的价值+0.01 Happy Programming Contest Time Limit: 2 Seconds      Memory Limit: 65536 KB In Zhejiang University Programming Contest, a team is called "couple team" if it consists of only two students loving each other. In the cont…