Daniel-Nikpayuk_SICP-Solutions/Chapter 1/1.2/exercise-1.16 (fast-expt)/exercise.lsp
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;; Copyright 2015 Daniel Nikpayuk
;;
;; This file is part of SICP Solutions.
;;
;; SICP Solutions is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License
;; as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
;;
;; SICP Solutions is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty
;; of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
;;
;; You should have received a copy of the GNU General Public License along with SICP Solutions. If not, see
;; <http://www.gnu.org/licenses/>.
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;fast exponentiation.

(define (square x) (* x x))

(define (fast-expt-i b n)
 (define (fast-expt prim sec n)
  (cond
   ((= n 0) prim)
   ((even? n) (fast-expt prim (square sec) (/ n 2)))
   (else (fast-expt (* prim sec) sec (- n 1)))
  )
 )
 (fast-expt 1 b n)
)

