PROPERTIES AND ARRAYS---------------------------------property lists and arrays* A procedure that creates data is a constructor.* A procedure that extracts data is a reader.* A procedure that changes data is a writer.-----------------------------------------------------------Symbol     Parents Property    Children Propertypatrick    (robert dorothy)    (sarah)karen      (james eve)         (sarah)-------------------------------------------------------------(get 
    
     
      )* (get 'patrick 'parents)(ROBERT DOROTHY)-----------------------------------------------------------(setf (get 
       
       
        ) 
        
         )* (setf (get 'patrick 'parents) '(robert dorothy))(ROBERT DOROTHY)------------------------------------------------------------(remprop 
          
          
           )* (setf (get 'bag 'contents) '(bread butter))(BREAD BUTTER)* (get 'bag 'contents)(BREAD BUTTER)* (remprop 'bag 'contents)T* (get 'bag 'contents)NIL題題題題題題題題題題題題題題題題題題題題題題題題題題題題題題題題題題題題題題題11-1: Assume that if a person's father is known, the father'sname is given as the value of the FATHER property. Define GRANDFATHER,a procedure that returns the name of a person's paternal grandfather, ifknown, or NIL otherwise.-------------------------------------------------------------------11-2: Define ADAM, a procedure that returns the most distant maleancestor of a person through the paternal line, working through theFATHER property. If no male ancestor is known, the procedure is toreturn the name given as its argument. For simplicity, assume that noname is ever used twice.--------------------------------------------------------------------11-3: Define ANCESTORS, a procedure that returns a list consisting ofthe person given as its argument together with all known ancestors ofthe person. It is to work through both the FATHER and MOTHER properties.You may assume that related people do not have children together; thatis, there is never a way to get to any ancestor by two distinct paths.----------------------------------------------------------------------11-4: Suppose each city in a network of cities and highways isrepresented by a symbol. Further suppose that each city has a propertynamed NEIGHBORS. The value of the NEIGHBORS property is a list of allthe other cities for which there is a direct highway connection.Define CONNECT, a procedure that takes two cities as arguments and putseach into a list which the value of the NEIGHBORS property of the other.Write CONNECT such if a connection is already in place, CONNECT changesnothing and returns NIL; otherwise CONNECT returns T.------------------------------------------------------------------------11-5: Suppose that the value of the position property is a list of two coordinates. Assuming a flat earth, write DISTANCE, a procedurethat calculates the distance between two cities based on the values oftheir POSITION properties. Remember that SQRT calculates square roots.-----------------------------------------------------------------------* (setf part-bins (make-array '(4)))* (setf checker-board (make-array '(8 8)))* (setf part-bins (make-array 4))* (setf part-bins (make-array 4 :initial-element 'e))#(E E E E)* (setf checker-board (make-array '(8 8)                    :initial-contents                    '(X B X B X B X B)                    (B X B X B X B X)                    (X B X B X B X B)                    (B X B X B X B X)                     (X E X E X E X E)                   (W X W X W X W X)                    (X W X W X W X W)                    (W X W X W X W X))))#2A((X B X B ...)    (B X B X ...)    (X B X B ...)    (E X E X ...)    ...)-----------------------------------------------------------* (aref part-bins 0)    ;Expression stored in place 0.EMPTY* (aref part-bins 3)    ;Expression stored in place 3.EMPTY* (aref checker-board 0 3)    ;Expression stored in place (0 3).B* (aref checker-board 3 0)    ;Expression stored in place (3 0).E---------------------------------------------------------------(setf (aref part-bins 0) 'nails)    ;Store expression in place 0.(Setf (aref part-bins 1) 'nuts)    ;Store expression in place 1.(setf (aref part-bins 2) 'bolts)    ;Store expression in place 2.(setf (aref part-bins 3) 'washers) ;Store expression in place 3.------------------------------------------------------------------(defun count-bins-with-specified-part (part) (let ((result 0))    (dotimes (n 4 result)    (when (eq part (aref part-bins n))        (setf result (+ result 1))))))* (count-bins-with-specified-part 'washers)1-----------------------------------------------------------------(defun count-elements-with specified-part (part array) (let ((result 0))    (dotimes (n (array-demension array 0) result)    (when (eq part (aref array n))        (setf result (+ result 1))))))題題題題題題題題題題題題題題題題題題題題題題題題題題題題題題題題題題題題題題題題題11-6: Write STATIC-VALUE, a procedure that counts the number ofwhite pieces minus the number of black pieces in the CHECKER-BOARDarray. Assume ordinary pieces are represented by W and B and kingsare represented by W-KING and B-BING. Also one king is worth two ordinary pieces.解解解解解解解解解解解解解解解解解解解解解解解解解解解解解解解解解解解解解解解解解解11-1:(defun grandfather (x)  (when (get x 'father)    (get (get x 'father) 'father)))The following, more efficient solution binds a LET parameter to thevalue returned by GET:(defun grandfather (x)  (let ((father (get x 'father)))    (when father      (get father 'father))))-------------------------------------------------------------------11-2:(defun adam (x) (if (get x 'father)    (adam (get x 'father))     x))-----------------------------------------------------------------11-3:(defun ancestors (x)  (when x    (cons x (append (ancestors (get x 'father))                    (ancestors (get x 'mother))))))------------------------------------------------------------------11-4:(defun connect (a b) (let ((a-neighbors (get a 'neighbors))    (b-neighbors (get b 'neighbors))        (result nil))    (unless (member b a-neighbors)       (setf (get a 'neighbors) (cons b a-neighbors))       (setf result t))    (unless (member a b-neighbors)       (setf (get b 'neighbors) (cons a b-neighbors))       (setf result t))    result))-----------------------------------------------------------------11-5:(defun distance (city-1 city-2) (let ((p1 (get city-1 'position))        (p2 (get city-2 'position))) (sqrt (+ (expt (- (first p1) (first p2)) 2)            (expt (- (second p1) (second p2)) 2)))))-----------------------------------------------------------------11-6: The following solution works, but inefficiently, inasmuch as it looks at the white squares, which cannot hold pieces:(defun static-value (board) (let ((result 0))    (dotimes (m 8 result)      (dotimes (n 8)        (cond ((eq 'white (aref board m n))               (setf result (+ 1 result)))              ((eq 'black (aref board m n))               (setf result (- result 1)))              ((eq 'white-king (aref board m n))               (setf result (+ result 2)))              ((eq 'black-king (aref board m n))               (setf result (- result 2))))))))How could you improve the efficiency of the procedure?