import java.math.BigInteger;
public class BigFraction
{
    private final BigInteger num;
    private final BigInteger denom;
    public BigFraction(BigInteger num, BigInteger denom)
    {
        if(denom.compareTo(BigInteger.ZERO) < 0)
        {
            num = num.negate();
            denom = denom.negate();
        }
        BigInteger d = num.gcd(denom);
        num = num.divide(d);
        denom = denom.divide(d);
        this.num = num;
        this.denom = denom;
    }
    /**
    * This static factory method produces a BigFraction
    * with specified numerator and denominator
    * @param num the numerator
    * @param denom the denominator
    * @return the BigFraction num/denom
    */
    public static BigFraction valueOf(long num, long denom)
    {
        return new BigFraction(BigInteger.valueOf(num),
            BigInteger.valueOf(denom));
    }
    @Override
    public String toString()
    {
        return String.format("%s/%s", num, denom);
    }
    public static void main(String[] args)
    {
        BigFraction f = BigFraction.valueOf(2,4);
        System.out.println(f);
        BigFraction g = BigFraction.valueOf(-2, -4);
        System.out.println(g);
    }
}