from fractions import gcd

t1 = int(input())
t2 = int(input())
t3 = int(input())
LCM12 = t1 * t2 // gcd(t1, t2)
LCM123 = LCM12 * t3 // gcd(LCM12, t3)

d = 1
for i in range(2, t3 + 1):
    if t1 % i == t2 % i == t3 % i:
        if gcd(i, LCM123) == 1:
            d = i
p = gcd(LCM123, d)
print('{}/{}'.format(LCM123//p, d//p))