; An alternative implementation of sumloop,
; that stores into the global variable only at the
; end of the loop, written by Will Clinger to test
; Kernighan and Van Wyk's conclusion that this has
; essentially the same performance as their benchmark.

(define sum 0)

(define (tail-rec-aux i n s)
  (if (< i n)
      (tail-rec-aux (+ i 1) n (+ s 1))
      (begin (set! sum s)
             sum)))

(define (tail-rec-loop n)
	(tail-rec-aux 0 n 0))

; (tail-rec-loop 1000000)