(in-package :cl-user)
(eval-when (:compile-toplevel :load-toplevel :execute)
  (sb-int:defconstant-eqx opt
    #+swank '(optimize (speed 3) (safety 2))
    #-swank '(optimize (speed 3) (safety 0) (debug 0))
    #'equal)
  #+swank (ql:quickload '(:cl-debug-print :fiveam) :silent t)
  #-swank (set-dispatch-macro-character
           #\# #\> (lambda (s c p) (declare (ignore c p)) `(values ,(read s nil nil t)))))
#+swank (cl-syntax:use-syntax cl-debug-print:debug-print-syntax)

(defmacro define-int-types (&rest bits)
  `(progn
     ,@(mapcar (lambda (b) `(deftype ,(intern (format nil "UINT~A" b)) () '(unsigned-byte ,b))) bits)
     ,@(mapcar (lambda (b) `(deftype ,(intern (format nil "INT~A" b)) () '(signed-byte ,b))) bits)))
(define-int-types 2 4 7 8 15 16 31 32 62 63 64)

(defconstant +mod+ 1000000007)

(defmacro dbg (&rest forms)
  #+swank (if (= (length forms) 1)
              `(format *error-output* "~A => ~A~%" ',(car forms) ,(car forms))
              `(format *error-output* "~A => ~A~%" ',forms `(,,@forms)))
  #-swank (declare (ignore forms)))

(declaim (inline println))
(defun println (obj &optional (stream *standard-output*))
  (let ((*read-default-float-format* 'double-float))
    (prog1 (princ obj stream) (terpri stream))))

;; BEGIN_INSERTED_CONTENTS
(defpackage :cp/quad-equation
  (:use :cl)
  (:export #:solve-quad-equation))
(in-package :cp/quad-equation)

;; TODO: handling for the cases a == 0
(declaim (inline solve-quad-equation))
(defun solve-quad-equation (a b c)
  "Solves ax^2 + bx + c = 0"
  (assert (not (zerop a)))
  (let* ((a (float a 1d0))
         (b (float b 1d0))
         (c (float c 1d0))
         (d (sqrt (- (* b b) (* 4 a c)))))
    (labels ((solve2 ()
               (return-from solve-quad-equation
                 (values (/ (+ (- b) d) (* 2 a))
                         (/ (- d b) (* 2 a)))))
             (nan-p (x)
               (and (typep x 'double-float)
                    (sb-ext:float-nan-p x))))
      (handler-bind ((arithmetic-error (lambda (_) (declare (ignore _)) (solve2))))
        (let ((result1 (/ (+ (abs b) d) (* 2 a))))
          (multiple-value-bind (res1 res2)
              (if (< b 0)
                  (values result1 (/ c (* a result1)))
                  (values (- result1) (/ c (* a (- result1)))))
            (if (or (nan-p res1) (nan-p res2))
                (solve2)
                (values res1 res2))))))))

;; BEGIN_USE_PACKAGE
(eval-when (:compile-toplevel :load-toplevel :execute)
  (use-package :cp/quad-equation :cl-user))
(in-package :cl-user)

;;;
;;; Body
;;;

(defun main ()
  (let* ((a (read))
         (b (read))
         (c (read))
         (desc (- (* b b) (* 4 a c))))
    (cond ((< desc 0) (write-line "imaginary"))
          ((zerop desc)
           (println (float (- (/ b (* 2 a))) 1d0)))
          (t
           (multiple-value-bind (root1 root2) (solve-quad-equation a b c)
             (when (> root1 root2)
               (rotatef root1 root2))
             (format t "~F ~F~%" root1 root2))))))

#-swank (main)

;;;
;;; Test and benchmark
;;;

#+swank
(defun get-clipbrd ()
  (with-output-to-string (out)
    #+os-windows (run-program "powershell.exe" '("-Command" "Get-Clipboard") :output out :search t)
    #+os-unix (run-program "xsel" '("-b" "-o") :output out :search t)))

#+swank (defparameter *this-pathname* (uiop:current-lisp-file-pathname))
#+swank (defparameter *dat-pathname* (uiop:merge-pathnames* "test.dat" *this-pathname*))

#+swank
(defun run (&optional thing (out *standard-output*))
  "THING := null | string | symbol | pathname

null: run #'MAIN using the text on clipboard as input.
string: run #'MAIN using the string as input.
symbol: alias of FIVEAM:RUN!.
pathname: run #'MAIN using the text file as input."
  (let* ((*standard-output* (or out (make-string-output-stream)))
         (res (etypecase thing
                (null
                 (with-input-from-string (*standard-input* (delete #\Return (get-clipbrd)))
                   (main)))
                (string
                 (with-input-from-string (*standard-input* (delete #\Return thing))
                   (main)))
                (symbol (5am:run! thing))
                (pathname
                 (with-open-file (*standard-input* thing)
                   (main))))))
    (if out res (get-output-stream-string *standard-output*))))

#+swank
(defun gen-dat ()
  (uiop:with-output-file (out *dat-pathname* :if-exists :supersede)
    (format out "")))

#+swank
(defun bench (&optional (out (make-broadcast-stream)))
  (time (run *dat-pathname* out)))

;; To run: (5am:run! :sample)
#+swank
(it.bese.fiveam:test :sample
  (it.bese.fiveam:is
   (equal "-3.449489742783178 1.449489742783178
"
          (run "1 2 -5
" nil)))
  (it.bese.fiveam:is
   (equal "2.000000000000000
"
          (run "1 -4 4
" nil)))
  (it.bese.fiveam:is
   (equal "imaginary
"
          (run "1 3 4
" nil))))