2013
11-08

# Exponentiation

Problems involving the computation of exact values of very large magnitude and precision are common. For example, the computation of the national debt is a taxing experience for many computer systems.

This problem requires that you write a program to compute the exact value of Rn where R is a real number ( 0.0 < R < 99.999 ) and n is an integer such that 0 < n <= 25.

The input will consist of a set of pairs of values for R and n. The R value will occupy columns 1 through 6, and the n value will be in columns 8 and 9.

The output will consist of one line for each line of input giving the exact value of R^n. Leading zeros should be suppressed in the output. Insignificant trailing zeros must not be printed. Don’t print the decimal point if the result is an integer.

95.123 12
0.4321 20
5.1234 15
6.7592  9
98.999 10
1.0100 12


548815620517731830194541.899025343415715973535967221869852721
.00000005148554641076956121994511276767154838481760200726351203835429763013462401
43992025569.928573701266488041146654993318703707511666295476720493953024
29448126.764121021618164430206909037173276672
90429072743629540498.107596019456651774561044010001
1.126825030131969720661201

If you don’t know how to determine wheather encounted the end of input:

s is a string and n is an integer
C++
while(cin>>s>>n)
{
...
}
c
while(scanf("%s%d",s,&n)==2) //to  see if the scanf read in as many items as you want
/*while(scanf(%s%d",s,&n)!=EOF) //this also work    */
{
...
}

方法（一）：
//* @author: [email protected]/* <![CDATA[ */!function(t,e,r,n,c,a,p){try{t=document.currentScript||function(){for(t=document.getElementsByTagName('script'),e=t.length;e--;)if(t[e].getAttribute('data-cfhash'))return t[e]}();if(t&&(c=t.previousSibling)){p=t.parentNode;if(a=c.getAttribute('data-cfemail')){for(e='',r='0x'+a.substr(0,2)|0,n=2;a.length-n;n+=2)e+='%'+('0'+('0x'+a.substr(n,2)^r).toString(16)).slice(-2);p.replaceChild(document.createTextNode(decodeURIComponent(e)),c)}p.removeChild(t)}}catch(u){}}()/* ]]> */
import java.util.Scanner;
import java.math.*;

public class Main{

public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
while (sc.hasNext()) {
BigDecimal bd = new BigDecimal(sc.next());
BigDecimal result = bd.pow(sc.nextInt());
String s = result.stripTrailingZeros().toPlainString();
if(s.startsWith("0"))
s=s.substring(1);
System.out.println(s);
}
}
}

import java.util.*;
import java.io.*;
import java.math.*;

public class Main {
public static void main(String[] args) {
Scanner scan = new Scanner(new BufferedReader(

while(scan.hasNext())
{
BigDecimal bd = scan.nextBigDecimal();
int p = scan.nextInt();

String str = bd.pow(p).toPlainString();

int endFlag = str.length();

for(int i = endFlag-1; i >= 0; i--)
{
if(str.contains(".") && str.charAt(i) == '0')
endFlag = i;
else
break;
}

str = str.substring(0, endFlag);
if(str.startsWith("0."))
str = str.substring(1);

if(str.endsWith("."))
str = str.substring(0,str.length()-1);
System.out.println(str);
}
}
}

1. 博主您好，这是一个内容十分优秀的博客，而且界面也非常漂亮。但是为什么博客的响应速度这么慢，虽然博客的主机在国外，但是我开启VPN还是经常响应很久，再者打开某些页面经常会出现数据库连接出错的提示

2. 有一点问题。。后面动态规划的程序中
int dp[n+1][W+1];
会报错 提示表达式必须含有常量值。该怎么修改呢。。

3. 约瑟夫也用说这么长……很成熟的一个问题了，分治的方法解起来o(n)就可以了，有兴趣可以看看具体数学的第一章，关于约瑟夫问题推导出了一系列的结论，很漂亮

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