let a1, a2, a3, b1, b2, b3 =
  Scanf.scanf "%f %f %f %f %f %f\n" @@ fun a b c d e f -> a, b, c, d, e, f
let () = print_endline
    (if int_of_float (a1**b1+.a2**b2+.a3**b3) mod 2 = 0 then ":-)" else ":-(")