let x1, y1, x2, y2 = Scanf.scanf " %d %d %d %d" @@ fun a b c d -> a, b, c, d
let dx, dy = x2 - x1, y2 - y1
let x3, y3 = x2 - dy, y2 + dx
let _ = Printf.printf "%d %d %d %d\n" x3 y3 (x3 - dx) (y3 - dy)