import math

t1, t2, t3 = [int(input()) for _ in range(3)]
mod = t1 * t2 * t3
a1 = (t2 - t1) * t3
a2 = (t3 - t2) * t1
q = math.lcm(mod // math.gcd(a1, mod), mod // math.gcd(a2, mod))
p = math.gcd(a1 * q // mod, a2 * q // mod)
g = math.gcd(p, q)
print(f"{q//g}/{p//g}")