def gcd(a, b):
    while b > 0:
        a, b = b, a % b
    return a

def lcm(a, b):
    return a * b // gcd(a, b)

T = [int(input()) for i in range(3)]
g = lcm(lcm(T[0],T[1]),T[2])
den = 0
for i in range(1,g):
    if g//T[0]%i == g//T[1]%i and g//T[1]%i == g//T[2]%i:
        den = i
# ig = g//gcd(g,den)
# iden = den//gcd(g,den)
print(str(g)+'/'+str(den))
# print(str(ig)+'/'+str(iden))
# print(*[g//T[i] for i in range(3)])