count change in mit-scheme

count-change.csm

(define (count-change coins amount)
  (display coins) (newline)
  (display amount) (newline)
  (cond 
    ((= 0 amount) 1)
    ((< amount 0) 0)
    ((null? coins) 0)
    (else 
      (+ 
        (count-change coins (- amount (car coins)))
        (count-change (cdr coins) amount)
      )
    )
  )
)