a,b,c = STDIN.map(&:to_i)
tmp = a.lcm(b.lcm(c))
a = tmp / a
b = tmp / b
c = tmp / c
MIN = [a,b,c].min
(MIN + 1).times{
    tmp2 = a.gcd(b.gcd(c))
    if tmp2 != 1
        puts Rational(tmp,tmp2)
        exit
    end
    a -= 1
    b -= 1
    c -= 1
    }
puts "#{tmp}/1"