fib.scm

(import (rnrs))
(define fib
  (lambda (n)
    (cond
      ((eq? 1 n) 1)
      ((eq? 2 n) 1)
      (else (+ (fib (- n 1)) (fib (- n 2)))))))
(display (fib 45))

; > /usr/bin/time scheme --script fib.scm
; 7.39user 0.01system 0:07.40elapsed 99%CPU (0avgtext+0avgdata 39180maxresident)k
; 0inputs+0outputs (0major+9387minor)pagefaults 0swaps

; > /usr/bin/time scheme --program fib.scm > /dev/null
; 5.92user 0.02system 0:05.95elapsed 99%CPU (0avgtext+0avgdata 39432maxresident)k
; 0inputs+0outputs (0major+8927minor)pagefaults 0swaps