hdu 1063 Exponentiation

http://acm.hdu.edu.cn/showproblem.php?pid=1063

import java.math.BigDecimal;
import java.util.*;
public class Main {
    public static void main(String []args)
    {
        Scanner cin=new Scanner(System.in);
        BigDecimal r,mutil;    
        String ans;
        int n;
        while(cin.hasNextBigDecimal())
        {
            r=cin.nextBigDecimal();
            n=cin.nextInt();
            mutil=r.pow(n);//乘方
            mutil=mutil.stripTrailingZeros();//去掉后导零
            ans=mutil.toPlainString();
            if(ans.indexOf('0')==0)
            {
                ans=ans.substring(1);//小于零去掉零
            }
            System.out.println(ans);
        }
    }

}