local function getgcd(x, y)
  while 0 < x do
    x, y = y % x, x
  end
  return y
end
local t1, t2, t3 = io.read("*n", "*n", "*n")
local a1 = t1 * (t3 - t2)
local a2 = t3 * (t2 - t1)
local gcd_a = getgcd(a1, a2)
local mul = math.floor(a2 / gcd_a)

local b1 = mul * t1 * t2
local b2 = t2 - t1
local gcd_b = getgcd(b1, b2)

b1 = math.floor(b1 / gcd_b)
b2 = math.floor(b2 / gcd_b)
print(b1 .. "/" .. b2)