x, y, z = 3.times.map{1/gets.to_r}
a = [1/(x+y), 1/(x-y)]
b = [1/(y+z), 1/(y-z)]
ans = Float::INFINITY
def _lcm(m, n)
  (m.numerator * n.denominator).lcm(m.denominator * n.numerator).to_r / (n.denominator * m.denominator)
end
a.each do |_a|
  b.each do |_b|
    r = _lcm(_a, _b)
    ans = r if ans > r
  end
end
puts "#{ans.numerator}/#{ans.denominator}"