hdu 1063 Exponentiation java

import java.io.*;

import java.math.*;
import java.util.*;
/**
*
* @author va
*/
public class Main {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        // TODO code application logic here
        Scanner cin = new Scanner(System.in);
        BigDecimal a;
        int n;
        while (cin.hasNextBigDecimal())
        {
            a = cin.nextBigDecimal();
            n = cin.nextInt();
            int i;
            BigDecimal b = new BigDecimal("1");
            for (i = 0; i < n; ++i)
            {
                b = b.multiply(a);
            }
            b = b.stripTrailingZeros();
            String str = b.toPlainString();
            if (str.startsWith("0."))

　　　　{
                str = str.substring(1);

　　　　}
            System.out.println(str);
        }
    }
}