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]) S = [g//T[i] for i in range(3)] den = 0 for i in range(1,g//min(S)): if S[0]%i == S[1]%i and S[1]%i == S[2]%i: den = i print(str(g)+'/'+str(den))