HDOJ 1063

Exponentiation

Time Limit: 1000/500 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 5659    Accepted Submission(s): 1554

Problem Description

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. 

 

Input

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.

 

Output

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.

 

Sample Input

95.123 120.4321 205.1234 156.7592  998.999 101.0100 12

 

Sample Output

548815620517731830194541.899025343415715973535967221869852721.0000000514855464107695612199451127676715483848176020072635120383542976301346240143992025569.92857370126648804114665499331870370751166629547672049395302429448126.76412102161816443020690903717327667290429072743629540498.1075960194566517745610440100011.126825030131969720661201

 

Source

East Central North America 1988

 

Recommend

PrincetonBoy

 

高精度的小数幂，注意去除前导零和后导零。

import java.io.*;import java.util.*;import java.math.*;/** * * @author XM_zhou */public class Main{    public static void main(String[] args)    {        Scanner cin = new Scanner(System.in);        int n;        String s;        BigDecimal ans;        while(cin.hasNext())        {            ans = cin.nextBigDecimal();            n = cin.nextInt();            ans = ans.pow(n);            ans = ans.stripTrailingZeros();            s = ans.toPlainString();            if(s.charAt(0) == '0')            {                System.out.println(s.substring(1));            }            else             {                System.out.println(s);            }        }    }}