class Fraction(private val numenator: Long, private val denominator: Long): Comparable<Fraction> {
    override fun compareTo(other: Fraction): Int {
        val diff = numenator * other.denominator - other.numenator * denominator
        return if (diff < 0) -1 else if (diff == 0L) 0 else 1
    }

    override fun toString(): String {
        return "$numenator/$denominator"
    }
}

fun readLongs() = readLine()!!.split(' ').map { it.toLong() }

fun gcd(a: Long, b: Long): Long {
    if (b == 0L) {
        return a
    }
    return gcd(b, a % b)
}

fun lcm(a: Long, b: Long) = (a / gcd(a, b)) * b

fun main() {
    val (a, b, c, d) = readLongs()
    val gcdAB = gcd(a, b)
    val gcdAC = gcd(a, c)
    val gcdAD = gcd(a, d)
    val gcdBC = gcd(b, c)
    val gcdBD = gcd(b, d)
    val gcdCD = gcd(c, d)

    val fractions = mutableListOf<Fraction>()
    fractions.add(Fraction(a, b))
    fractions.add(Fraction(a, c))
    fractions.add(Fraction(a, d))

    fractions.add(Fraction(b, a))
    fractions.add(Fraction(b, c))
    fractions.add(Fraction(b, d))

    fractions.add(Fraction(c, a))
    fractions.add(Fraction(c, b))
    fractions.add(Fraction(c, d))

    fractions.add(Fraction(d, a))
    fractions.add(Fraction(d, b))
    fractions.add(Fraction(d, c))

    fractions.sort()
    println(fractions[1])
}