;;;This function recurs down a list of markers and a list. If any of the elements of the list of markers occurs in the list the number that the function returns is increased by one.
(define occurN
  (lambda (markers l)
    (cond
     ((or (null? markers) (null? l)) 0)
     ((atom? (car markers))
      (cond
       ((eq? (car markers) (car l))
        (+ 1 (occurN markers (cdr l))
           (occurN (cdr markers) (cdr l))))
      (else (occurN (cdr markers) (cdr l))))))

(occurN '(bananas kiwis) '((curry '() (chicken) '())))
;;;This works fine
(occurN '(bananas kiwis) '(peaches apples bananas))
;;;This returns 0 which it should return 1

(define (occurN markers l)
    (define (helper marker lst)
      (cond ((null? lst) 0)
	    ((eq? marker (car lst)) (+ 1 (helper marker (cdr lst))))
	    (else (helper marker (cdr lst)))))
    (if (null? markers) 0
	(+ (helper (car markers) l) (occurN (cdr markers) l))))

(define occurN
  (lambda (markers l)
    (cond
     ((or (null? markers)
          (null? l))
      0)
     ((not (pair? (car markers)))
      (cond
       ((eq? (car markers) (car l))
        (+ 1 (occurN markers (cdr l))
           (occurN (cdr markers) (cdr l))))
       
       (else
        (+ (occurN markers (cdr l))
           (occurN (cdr markers) l))))))))