;;; 2.6.scm
;;; $Id: 2.6.scm 1.2 2023/04/02 10:53:15 s Exp $

(define (main args)
  ; input
  (define r 0.12)
  (define i1 (list 0 1 2 3 4 5 ))
  (define i2 (list 0 1 2 3 4 5 ))
  (define i3 (list 0 1 2 3 4 5 5 6 7 8 9 10 11))
  (define i4 (list 0 1 2 3 4 5 5 6 7 8 9 10 11))
  (define c1 (list -1000 -1000 -1000 -1000 -1000 -1000))
  (define c2 (list -1900  -900  -900  -900  -900  -900))
  (define c3 (list -1000 -1000 -1000 -1000 -1000 -1000 
                   -1000 -1000 -1000 -1000 -1000 -1000))
  (define c4 (list -1900 -1000 -1000 -1000 -1000 -1000 
                   -1000 -1000 -1000 -1000 -1000 -1000))
  ;function
  (define (sum x) (fold + 0 x))
  (define (df r i) (/ (expt (+ 1 (/ r 12 )) i)))
  (define (pv r i c) (sum (map (lambda (x y) (* x (df r y))) c i)))
  ; output
  (print "2.6")
  (print "c1= " c1)
  (print "c2= " c2)
  (print "c3= " c3)
  (print "c4= " c4)
  (print "pv1($)= " (pv r i1 c1))
  (print "pv2($)= " (pv r i2 c2))
  (print "pv3($)= " (pv r i3 c3))
  (print "pv4($)= " (pv r i4 c4))
0)
;;; end