import sys
from math import gcd
sys.setrecursionlimit(10**7)
def I(): return int(sys.stdin.readline().rstrip())
def MI(): return map(int,sys.stdin.readline().rstrip().split())
def LI(): return list(map(int,sys.stdin.readline().rstrip().split()))
def LI2(): return list(map(int,sys.stdin.readline().rstrip()))
def S(): return sys.stdin.readline().rstrip()
def LS(): return list(sys.stdin.readline().rstrip().split())
def LS2(): return list(sys.stdin.readline().rstrip())


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


T1,T2,T3 = I(),I(),I()
a = T1*lcm(T2*(T3-T1),T3*(T2-T1))
b = (T2-T1)*(T3-T1)
g = gcd(a,b)

print('{}/{}'.format(a//g,b//g))