(define (fib n)
   (cond
      ((< n 1) 0)
      ((or (equal? n 1) (equal? n 2)) 1)
      (else (+ (fib (- n 2))(fib (- n 1))))))
 
(define (member-nl n-list member)
  (cond
    ((null? n-list)        #f)
    ((equal? member 
             (car n-list)) #t)
    ((list? (car n-list))  (or (member-nl (car n-list) 
                                          member)
                               (member-nl (cdr n-list) 
                                          member)))
    (else                  (member-nl (cdr n-list) 
                                      member))))





 (define (test-this expression result)
  (if (equal? (eval expression) result)
      (begin 
        (display expression)
        (display " => ")
        (display result)
        (display " passed")
        (newline))
      (begin 
        (display "VVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVV")
        (newline)
        (display "FAILURE--->> ")
        (display expression)
        (display " => ")
        (display (eval expression))
        (display " (expected ")
        (display result)
        (display ")")
        (display " <<---FAILURE")
        (newline)
        (display "^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^")
        (newline))))
 

(display "Testing fib" ) 
(newline)
 (test-this '(fib 5) 5 )
 (test-this '(fib 2) 2 )
 (test-this '(fib 2) 1 )
 (test-this '(fib 3) 2 )
(test-this '(fib 0) 0)
(test-this '(fib -1) 0)
(test-this '(fib -6) 0)
(test-this '(fib -22) 0)
(test-this '(fib 1) 1)
(test-this '(fib 2) 1)
(test-this '(fib 3) 2)
(test-this '(fib 4) 3)
(test-this '(fib 19) 4181)
(test-this '(fib 23) 28657)

(newline)
(newline)
(display "Testing member-nl")
(newline)
(test-this '(member-nl '((3 3 4) 8  3) 8) #t)
(test-this '(member-nl '((3 3 4) 8  3) 14) #f)
(test-this '(member-nl '((3 3 4) 8  3) 4) #t )
(test-this '(member-nl () 'a) #f)
(test-this '(member-nl '(3 a) 3) #t)
(test-this '(member-nl '(3 #f 5) #f) #t)