countchange.scm

(define (count-change amount)
    (cc amount 5))

(define (cc amount kinds-of-coins)
    (cond ((= amount 0) 1)
        ((or (< amount 0) (= kinds-of-coins 0)) 0)
        (else (+ (cc amount 
                    (- kinds-of-coins 1))
                (cc (- amount 
                        (first-denominaton kinds-of-coins))
                        kinds-of-coins)))))

(define (first-denominaton kinds-of-coins)
    (cond ((= kinds-of-coins 1) 1)
          ((= kinds-of-coins 2) 5)
          ((= kinds-of-coins 3) 10)
          ((= kinds-of-coins 4) 25) 
          ((= kinds-of-coins 5) 50)))