import java.math.BigInteger;
import java.util.HashMap;

public class BytelandianMaxSum {
    private static HashMap<BigInteger, BigInteger> memory = new HashMap<BigInteger, BigInteger>();

    // The idea is to increase readability in the changer method and improve(?)
    // performance due to not constantly having to create new BigIntegers with
    // the same values

    public static final BigInteger FOUR = new BigInteger("4");
    public static final BigInteger THREE = new BigInteger("3");
    public static final BigInteger TWO = new BigInteger("2");

    public static void main(String[] args) {
        memory.put(new BigInteger("0"), new BigInteger("0"));
        BigInteger target = new BigInteger("100000000");
        System.out.println("The maximal value of " + target + " is "
                + changer(target).toString());

    }

    private static BigInteger changer(BigInteger coin) {
        if (memory.get(coin) != null) {
            return memory.get(coin);
        }
        BigInteger tmp = changer(coin.divide(FOUR)).add(
                changer(coin.divide(THREE)).add(changer(coin.divide(TWO))));
        return (tmp.compareTo(coin) == 1) ? tmp : coin;
    }

}