(defconstant +diff+ 100000)

(defun main (&rest argv)
  (declare (ignorable argv))
  (let* ((a (read))
         (b (read))
         (c (float a 1d0))
         (d 0d0))
    (loop while (< c b)
          do (incf d (/ (float (abs (* (- c a) (- c b))) 1d0) +diff+))
             (incf c (/ 1d0 +diff+)))    
    (format t "~f~%" d)))

(main)