#!/usr/bin/python3
from math import gcd
from fractions import Fraction
from functools import reduce
lcm = lambda a, b: a * b // gcd(a, b)
gcdx = lambda *arr: reduce(gcd, arr)
lcmx = lambda *arr: reduce(lcm, arr)

# a < b < c
a, b, c = map(int, (input() for _ in range(3)))
l = lcmx(a, b, c)
# x > y > z
x, y, z = l//a, l//b, l//c
g = gcdx(x-y, x-z, y-z)
res = Fraction(l, g)
print('{}/{}'.format(res.numerator, res.denominator))