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
PWM的实现过程中使用了两个计数器CNT 1和CNT2，通过技术比较来判定LED灯泡是否点亮:若CNT1<CNT2 ，LED灯泡由熄灭状态进入点亮状态 若CNT1>CNT2则LED灯泡由点亮状态进入熄灭状态。各基色LED灯泡是串行连接的，并且只需改变一种基色LED灯泡的状态便能实现色彩的变换，因此，系统计数器CNT1和CNT2只设立一组。如果当前改变的是红色LED灯泡的亮度，那么绿色和蓝色LED灯泡的亮度保持原状态不变。 系统计数器的另一个作用是控制色彩变换的频率，它可以由系统的初始值设定，也可以由用户来设定
上传时间： 2014-12-21
上传用户：SimonQQ
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
本程序为ARMLPC2292 SPWM调制程序，且已调试通过，功能为两路PWM调制输出，控制全桥逆变电路
上传时间： 2014-12-08
上传用户：yy541071797
有关电力电子的课件，是讲逆变电路的，用得上的看看吧
标签： 电力电子
上传时间： 2014-01-07
上传用户：wkchong
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
SPMC75 CPU ，产生３００点SPWM，经实验直接可连接控制变频逆变，unSP IDE 平台
上传时间： 2013-12-10
上传用户：wang0123456789
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
SED1335驱动320x240图形液晶驱动演示程序 接口情况表述： No: LCM ----- 52 --------------------- 1...VSS..... GND 地线 2...VDD..... +5V(VCC) 电源 3...VO ..... -Vadj Input 对比度负压调整输入 4...A0 ..... P2.0 寄存器选择信号,命令数据方式选择 5.../WR..... WR 写有效 6.../RD..... RD 读有效 7...D0 ..... P0.0 数据总线 D0 8...D1 ..... P0.1 数据总线 D1 9...D2 ..... P0.2 数据总线 D2 10..D3 ..... P0.3 数据总线 D3 11..D4 ..... P0.4 数据总线 D4 12..D5 ..... P0.5 数据总线 D5 13..D6 ..... P0.6 数据总线 D6 14..D7 ..... P0.7 数据总线 D7 15../CS .... GND 片选通信号，低电平有效.实际使用应编入地址 16../RES.... /RESET 复位信号，低电平有效，阻容式复位电路 17..VEE..... -Vout 逆变-22.5V 负电压输出 18..VSS..... GND 地线 0V
上传时间： 2013-12-22
上传用户：redmoons
一些关于svpwm的论文，有仿真的，也有设计逆变器的，大部分是网上收费的
上传时间： 2014-01-22
上传用户：kikye
