java power of 2

Because Java has a convenient String integer.tobinarystring (int), when learning to generate a subset of the algorithm to generate a power set with a bit string, think of Java implementation. Power set is very useful when solving knapsack problem, brute force method, simple and rough effective, of course, limited to sm

1 ImportJava.util.Scanner;2 3 Public classC {4 Public Static LongPowerintXintN) {5 if(n = = 0)6 return1;7 Longt = Power (X,N/2);8t = t*T;9 if(n%2 = = 1)Tent = t*x; One returnT; A } - Public Static voidMain (string[] args) { - //TODO auto-generated Metho

High precision Power time limit: Ms | Memory limit: 65535 KB Difficulty: 2 Describe It is a very common problem to calculate high-precision numbers with large numbers and high precision. For example, the calculation of national debt is a question of this kind.Now the problem you're solving is: for a real number R (0.0 Input input has mor

Power node Java learning materials Baidu Cloud:http://pan.baidu.com/s/1pJ4qNph650) this.width=650; "src=" http://s1.51cto.com/wyfs02/M02/77/D5/wKiom1ZvdFmxPZH8AADs-rDFfEo191.jpg "style=" float: none; "title=" 3.jpg "alt=" Wkiom1zvdfmxpzh8aads-rdffeo191.jpg "/>650) this.width=650; "src=" http://s2.51cto.com/wyfs02/M02/77/D4/wKioL1ZvdGOBMqq4AAIVXuzxlZk749.jpg "style=" float: none; "title=" 1.jpg "alt=" Wkiol1

1 PackageisPowerOfThree326;2 /*3 Given An integer, write a function to determine if it is a power of three.4 */5 Public classSolution {6 /*7 //The problem is understood incorrectly and understood as 3 times8 Public Static Boolean ispowerofthree (int n) {9 if (n==1)Ten return true; One else{ A for (int i=2;i - if (n%i==0) { - n=n/i; the if (n%i==0) { - n=n/i; - if (n%i==0) { - n=n/i; + return Ispowero

For example, first entering 2 4 is the calculation of 2 of the 4 parties, if there is a negative number, throw an exceptionThe code is as follows:ImportJava.util.*;ImportJava.util.Scanner;classMycalculator {LongPowerintNintPthrowsException {if(N ) { Throw NewException ("N and p should be non-negative"); } Else { return(Long) Math.pow (n, p); } }}classSolution { Public Static voidMai

substring.Thrown:Indexoutofboundsexception -if beginindex is negative, or endIndex is greater than the length of this String object,or Beginindex greater than endIndex. AC Code:Import Java.math.bigdecimal;import Java.util.scanner;public class Main {public static void main (string[] args) {Scanner s c = new Scanner (system.in), while (Sc.hasnext ()) {BigDecimal a = Sc.nextbigdecimal (); int b = Sc.nextint (); a = A.pow (b); String str = A.striptrailingzeros (). toplainstring (); if (Str.startsw

Power node Java Training What is a Web container? Provides an environment for the application components (Jsp,servlet) in which the Jsp,servlet directly and the environment variables in the container are connected to each other without concern for other system problems. There are mainly Web servers to implement. For example: Tomcat,weblogic,websphere and so on. The interface provided by this container stric

　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　A + b　(Sigma (ai^x))% mod1 ImportJava.util.*;2 Importjava.math.*;3 ImportJava.io.*;4 Public classMain5 {6 StaticBigInteger mod=NewBigInteger ("10000000007");7 Public Static voidMain (string[] args)8 {9 //for a large number of inputs, the following may be faster. TenScanner cin=NewScanner (NewBufferedinputstream (system.in)); One intT,n; A BigInteger k,sum,x; -t=cin.nextint (); - whi

The common design pattern of "Power node Java training "The four design patterns in Java:Factory(Factory mode ), builder(build mode) , Factorymethod (Factory approach mode),Prototype(original model mode), Singleton(singleton mode ), facade(façade mode ),Adapter(Adapter mode) , bridge(bridge mode ), Composite(synthetic mode ),Decorator(Decorative mode ), Flyweight(enjoy meta mode ), proxy(proxy mode ),comman

"Power node Java training " final, finally, finalize the differenceFinal is used to declare properties, methods, and classes, respectively, that the property is immutable, that the method is not overridden, and that the class is not inheritable. Finally is part of the exception-handling statement structure, which indicates that it is always executed. Finalize is a method of the object class that, when execu

http://my.oschina.net/kingfire/blog/156764OverviewRemote Power On (Wake Onlan) refers to the network implementation of the server or PC to start running, now a lot of network cards are supported by this feature. The simple principle is to send a specially formatted packet to the target host, and then start the system after the target host receives it.Specific methods. Setting the BIOS on Wake Onlan (WOL) feature View the MAC address of th

Power of High Precision Time limit:500 ms Memory limit:10000 K Total submissions:117394 Accepted:28569 DescriptionIt is a very common problem to perform high-precision calculation on numbers with large numbers and high precision. For example, calculating national debt is a problem of this type. The problem you want to solve now is: for a real number R (0.0 InputT input includes multiple groups of R and N. The R

Topic links1 ImportJava.util.*;2 Importjava.math.*;3 Public classmain{4 5 Public Static voidMain (string[] args) {6Scanner cin =NewScanner (system.in);7 while(Cin.hasnext ()) {8BigDecimal numa =cin.nextbigdecimal ();9 intnumb =cin.nextint ();TenString str =Numa.pow (Numb). Striptrailingzeros (). toplainstring (); One if(Str.startswith ("0.")) {//If the start is 0. Then start the output from the small points ASyst

Based on the HttpClient download page, followed by the URL should be extracted, the first I used is htmlpraser, after a few days, I found that there are jsoup this package, very useful, and then I will directly use Jsoup To crawl the page and extract the URL inside, here to share the code with you.Import Java. IO. IOException;Import Java. Util. HashSet;Import Java