1-9-recursion.scm

; Exercise 1.9.


;(define (+ a b)
; (if (= a 0)
;     b
;     (inc (+ (dec a) b))))

;(+ 4 5)
;(inc (+ 3 5))
;(inc (inc (+ 2 5)))
;(inc (inc (inc (+ 1 5))))
;(inc (inc (inc (inc (+ 0 5)))))
;(inc (inc (inc (inc 5))))
;(inc (inc (inc 6)))
;(inc (inc 7))
;(inc 8)
;9
;So it's recursive.

;(define (+ a b)
; (if (= a 0)
;     b
;     (+ (dec a) (inc b))))

;(+ 4 5)
;(+ 3 6)
;(+ 2 7)
;(+ 1 8)
;(+ 0 9)
;9
;So it's linear.