a,b,c = STDIN.map(&:to_i)
tmp = a.lcm(b.lcm(c))
a = tmp / a
b = tmp / b
c = tmp / c
[a,b,c].min.downto(2){|i|
    x = a % i
    y = b % i
    z = c % i
    if x == y && y == z
        tmp2 = tmp.gcd(i)
        puts "#{tmp / tmp2}/#{i / tmp2}"
        exit
    end
}
puts "#{tmp}/1"