The government of a small but important country has decided that the alphabet needs to be streamlined and reordered. Uppercase letters will be eliminated. They will issue a royal decree in the form of a String of B and A characters. The first character in the decree specifies whether a must come ( B )Before b in the new alphabet or ( A )After b . The second character determines the relative placement of b and c , etc. So, for example, "BAA" means that a must come Before b , b must come After c , and c must come After d . Any letters beyond these requirements are to be excluded, so if the decree specifies k comparisons then the new alphabet will contain the first k+1 lowercase letters of the current alphabet. Create a class Alphabet that contains the method choices that takes the decree as input and returns the number of possible new alphabets that conform to the decree. If more than 1,000,000,000 are possible, return -1. Definition
标签: government streamline important alphabet
上传时间: 2015-06-09
上传用户:weixiao99
第一章 概述 辨识(Identification)、状态估计和控制理论在现代控制理论中是密不可分的,它们互相渗透。辨识和状态估计离不开控制理论的支持,控制理论的应用几乎不能没有辨识和估计技术。由此可见,辨识在科研与实际应用领域都有很高的实用价值。 所谓辨识,就是从含有噪声的输入、输出数据中提取被研究对象的数据模型。此数据模型只是过程的输入输出特性在某种意义下的近似,而近似的准确度一般取决于采样数据的精度以及辨识方法的合理性。 辨识的目的是根据过程所提供测量的数据等信息,在某种准则意义下,估计出模型的未知参数,其基本原理如图1.1所示:
标签: Identification 控制理论 辨识 状态
上传时间: 2014-01-09
上传用户:aig85
电力系统在台稳定计算式电力系统不正常运行方式的一种计算。它的任务是已知电力系统某一正常运行状态和受到某种扰动,计算电力系统所有发电机能否同步运行 1运行说明: 请输入初始功率S0,形如a+bi 请输入无限大系统母线电压V0 请输入系统等值电抗矩阵B 矩阵B有以下元素组成的行矩阵 1正常运行时的系统直轴等值电抗Xd 2故障运行时的系统直轴等值电抗X d 3故障切除后的系统直轴等值电抗 请输入惯性时间常数Tj 请输入时段数N 请输入哪个时段发生故障Ni 请输入每时段间隔的时间dt
上传时间: 2015-06-13
上传用户:it男一枚
图像模板匹配计算,逐象素移动计算当前模板数据,提取图像特征点
上传时间: 2013-12-21
上传用户:GHF
上下文无关文法(Context-Free Grammar, CFG)是一个4元组G=(V, T, S, P),其中,V和T是不相交的有限集,S∈V,P是一组有限的产生式规则集,形如A→α,其中A∈V,且α∈(V∪T)*。V的元素称为非终结符,T的元素称为终结符,S是一个特殊的非终结符,称为文法开始符。 设G=(V, T, S, P)是一个CFG,则G产生的语言是所有可由G产生的字符串组成的集合,即L(G)={x∈T* | Sx}。一个语言L是上下文无关语言(Context-Free Language, CFL),当且仅当存在一个CFG G,使得L=L(G)。 *⇒ 例如,设文法G:S→AB A→aA|a B→bB|b 则L(G)={a^nb^m | n,m>=1} 其中非终结符都是大写字母,开始符都是S,终结符都是小写字母。
标签: Context-Free Grammar CFG
上传时间: 2013-12-10
上传用户:gaojiao1999
We have a group of N items (represented by integers from 1 to N), and we know that there is some total order defined for these items. You may assume that no two elements will be equal (for all a, b: a<b or b<a). However, it is expensive to compare two items. Your task is to make a number of comparisons, and then output the sorted order. The cost of determining if a < b is given by the bth integer of element a of costs (space delimited), which is the same as the ath integer of element b. Naturally, you will be judged on the total cost of the comparisons you make before outputting the sorted order. If your order is incorrect, you will receive a 0. Otherwise, your score will be opt/cost, where opt is the best cost anyone has achieved and cost is the total cost of the comparisons you make (so your score for a test case will be between 0 and 1). Your score for the problem will simply be the sum of your scores for the individual test cases.
标签: represented integers group items
上传时间: 2016-01-17
上传用户:jeffery
The XML Toolbox converts MATLAB data types (such as double, char, struct, complex, sparse, logical) of any level of nesting to XML format and vice versa. For example, >> project.name = MyProject >> project.id = 1234 >> project.param.a = 3.1415 >> project.param.b = 42 becomes with str=xml_format(project, off ) "<project> <name>MyProject</name> <id>1234</id> <param> <a>3.1415</a> <b>42</b> </param> </project>" On the other hand, if an XML string XStr is given, this can be converted easily to a MATLAB data type or structure V with the command V=xml_parse(XStr).
标签: converts Toolbox complex logical
上传时间: 2016-02-12
上传用户:a673761058
GPS观测值文件(RINEX)的读取,对观测值文件数据的提取,可结合导航电文的读取进行卫星定位与导航
上传时间: 2013-12-27
上传用户:hn891122
汉诺塔!!! Simulate the movement of the Towers of Hanoi puzzle Bonus is possible for using animation eg. if n = 2 A→B A→C B→C if n = 3 A→C A→B C→B A→C B→A B→C A→C
标签: the animation Simulate movement
上传时间: 2017-02-11
上传用户:waizhang
将魔王的语言抽象为人类的语言:魔王语言由以下两种规则由人的语言逐步抽象上去的:α-〉β1β2β3…βm ;θδ1δ2…-〉θδnθδn-1…θδ1 设大写字母表示魔王的语言,小写字母表示人的语言B-〉tAdA,A-〉sae,eg:B(ehnxgz)B解释为tsaedsaeezegexenehetsaedsae对应的话是:“天上一只鹅地上一只鹅鹅追鹅赶鹅下鹅蛋鹅恨鹅天上一只鹅地上一只鹅”。(t-天d-地s-上a-一只e-鹅z-追g-赶x-下n-蛋h-恨)
上传时间: 2013-12-19
上传用户:aix008