perm filename QUEEN.STR[LSP,JRA] blob sn#099704 filedate 1974-04-30 generic text, type T, neo UTF8
NIL 


(DEFPROP BASE 
 (NIL . 10.) 
VALUE)

(DEFPROP IBASE 
 (NIL . 10.) 
VALUE)

(DEFPROP PICKIT 
 (LAMBDA(L N)
  (PROG (M I J L1)
	(SETQ J (ADD1 (LENGTH L)))
   L1   (SETQ I 1.)
	(SETQ L1 L)
   L    (COND ((NULL L1) (RETURN N))
	      ((OR (EQ (CAR L1) N)
		   (EQ (PLUS (CAR L1) I) (PLUS N J))
		   (EQ (DIFFERENCE (CAR L1) I) (DIFFERENCE N J)))
	       (GO AGAIN)))
	(SETQ L1 (CDR L1))
	(SETQ I (ADD1 I))
	(GO L)
   AGAIN
	(SETQ N (ADD1 N))
	(COND ((GREATERP N 8.) (RETURN NIL)))
	(GO L1))) 
EXPR)

(DEFPROP QUEEN 
 (LAMBDA(ANS)
  (PROG (N)
	(COND ((EQ (LENGTH ANS) 8.) (RETURN ANS)))
	(SETQ N 1.)
   LL   (PRINT (LIST ANS N))
	(SETQ M (PICKIT ANS N))
	(COND (M (SETQ N (QUEEN (APPEND ANS (LIST M))))) (T (RETURN ANS)))
	(COND ((EQ (LENGTH N) 8.) (RETURN N)))
	(SETQ N (ADD1 (CAR (LAST N))))
	(COND ((GREATERP N 8.) (RETURN ANS)))
	(GO LL))) 
EXPR)

NIL