anchor.diff:  				(setf listadevars (append listadevars (list (write-to-string cont))))
   				
   				(if (not (equal NIL (aref arr i j) ))
  -				(setf listaderestr (append listaderestr (list (cria-restricao (GetNeighboursOfArrayCell aux i j) (CriaPredicado aux i j) )) ) )
  +				    (setf listaderestr
  +				          (append listaderestr
  +				                    (list (cria-restricao (GetNeighboursOfArrayCell aux i j)
  +				                                          (CriaPredicado aux i j)
  +                                          )
  +                                    )
  +                          )
  +                    )
   				)
   				(incf cont)
   			)
  
positive.code: 
  (defun procura-retrocesso-simples (psr)
    (cond ((notany #'zerop psr)
       (if (psr-consistente-p psr)
           psr
           nil))
      (t (let ((positions (fill-a-pix->psr psr)))
           (loop for position in positions
            do (loop for number in '(1 2 3 4 5 6 7 8 9)
                do (let ((result (procura-retrocesso-simples
                          (psr->fill-a-pix psr
                              lin
                              col))))
                     (when result
                   (return-from procura-retrocesso-simples result)))))))))
negative.code: 	 (setf sumaux soma) (if (and (<= sumaux valor) (>= (- 9 nzeros) valor)) T ))))
  	 
  	fun
  	)
  )	
  
  (defun fill-a-pix->psr (arr)
  	(let (
  