def gcd(a,b):
    if b<a:
        return gcd(b,a)
    if b%a==0:
        return a
    return gcd(b%a,a)

def f(a,b,c,d):
    g=gcd(a*d,b*c)
    bunshi = a*d*b*c/g
    bunbo = b*d
    g= gcd(bunbo,bunshi)
    return bunshi/g,bunbo/g
T1=int(raw_input())
T2=int(raw_input())
T3=int(raw_input())
a,b=f(T1*T2,T1+T2,T1*T3,T1+T3)
#print a,b
c,d=f(T1*T2,T1+T2,T1*T3,T3-T1)
#print c,d
if a*d > b*c:
    a,b=c,d
c,d=f(T1*T2,T2-T1,T1*T3,T1+T3)
#print c,d
if a*d > b*c:
    a,b=c,d
c,d=f(T1*T2,T2-T1,T1*T3,T3-T1)
#print c,d
if a*d > b*c:
    a,b=c,d
print "%d/%d"%(a,b)