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
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.
Threads are essential to Java programming, but learning to use them effectively is a nontrivial task. This new edition of the classic Java Threads shows you how to take full advantage of Java s threading facilities and brings you up-to-date with the watershed changes in Java 2 Standard Edition version 5.0 (J2SE 5.0). It provides a thorough, step-by-step approach to threads programming.
1. 下列說法正確的是 （ ）
A. Java語言不區分大小寫
B. Java程序以類為基本單位
C. JVM為Java虛擬機JVM的英文縮寫
D. 運行Java程序需要先安裝JDK
2. 下列說法中錯誤的是 ( )
A. Java語言是編譯執行的
B. Java中使用了多進程技術
C. Java的單行注視以//開頭
D. Java語言具有很高的安全性
3. 下面不屬于Java語言特點的一項是( )
A. 安全性
B. 分布式
C. 移植性
D. 編譯執行
4. 下列語句中，正確的項是 ( )
A . int $e,a,b=10
B. char c,d=’a’
C. float e=0.0d
D. double c=0.0f
We analyze, both analytically and numerically, the effectiveness
of cloaking an infinite cylinder from observations by electromagnetic
waves in three dimensions. We show that, as truncated approximations
of the ideal permittivity and permeability tensors tend towards
the singular ideal cloaking fields, so that the anisotropy ratio tends to
infinity, the D and B fields blow up near the cloaking surface. Since
the metamaterials used to implement cloaking are based on effective
medium theory, the resulting large variation in D and B will pose a
challenge to the suitability of the field averaged characterization of "
and 碌. We also consider cloaking with and without the SHS (softand-
hard surface) lining, shown in [6] to be theoretically necessary
for cloaking in the cylindrical geometry. We demonstrate numerically
that cloaking is significantly improved by the SHS lining, with both
the far field of the scattered wave significantly reduced and the blow
up of D and B prevented.
Ksplice is practical technology for updating the Linux kernel without rebooting. It enables you to avoid the disruptive process of rebooting for kernel security updates and bugfixes. By making it easy to keep your systems up to date, Ksplice helps you avoid the security and stability risks of running out-of-date software.
If you want to use the Struts Framework to its fullest potential, this is the book for you. Programming Jakarta Struts, 2nd Edition covers everything the successful earlier edition did as well as plenty more: now fully up to date with Struts 1.1, this edition covers the latest material on tag libraries and the new JavaServerFaces (JSF) APIs and even includes all-new chapters on JSF, JSTL/EL, and security.
