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package com.google.code.projecteuler;

import java.math.BigDecimal;
import java.util.Date;

/**
 * 2^15 = 32768 and the sum of its digits is 3 + 2 + 7 + 6 + 8 = 26.
 * 
 * <p/>
 * 
 * What is the sum of the digits of the number 2^1000?
 * 
 * @link <a
 *       href="http://projecteuler.net/index.php?section=problems&id=16">Problem
 *       16</a>
 * @author Cesar Arevalo
 */
public class Problem016 {

	public static void main(String[] args) {
		Date startDate = new Date();
		System.out.println("startDate: " + startDate.getTime());

		int base = 2;
		int power = 1000;
		BigDecimal baseToThePowerOf = new BigDecimal(base);
		baseToThePowerOf = baseToThePowerOf.pow(power);

		System.out.println("twoToThePowerOf1000: " + baseToThePowerOf);

		String baseToThePowerOfString = baseToThePowerOf.toString();

		System.out.println("twoToThePowerOf1000String: "
				+ baseToThePowerOfString);

		int sumOfDigits = 0;

		for (int i = 0; i < baseToThePowerOfString.length(); i++) {
			sumOfDigits += Integer.valueOf(baseToThePowerOfString.substring(i,
					i + 1));
		}

		System.out.println("sumOfDigits: " + sumOfDigits);

		Date endDate = new Date();
		System.out.println("endDate: " + endDate.getTime());
		System.out.println("time in millis: "
				+ (endDate.getTime() - startDate.getTime()));
	}
}