#!/usr/bin/env python3
# -*- coding: utf-8 -*-

import fractions
import itertools
import math


def lcm(x, y):
    return x // math.gcd(x, y) * y


def fraclcm(f1, f2):
    n1, d1 = f1.numerator, f1.denominator
    n2, d2 = f2.numerator, f2.denominator
    d = lcm(d1, d2)
    n1 *= d // d1
    n2 *= d // d2
    c = lcm(n1, n2)
    return fractions.Fraction(c, d)


def solve(fs):
    cands = [1 / abs(x - y) for x, y in itertools.combinations(fs, 2)]
    return fraclcm(cands[0], fraclcm(cands[1], cands[2]))


def main():
    fs = [fractions.Fraction(1, x) for x in (int(input()) for _ in range(3))]
    ans = solve(fs)
    print("{}/{}".format(ans.numerator, ans.denominator))


if __name__ == '__main__':
    main()