SICP 問題 2.45
(define (split first second) (lambda (painter n) (if (= n 0) painter (let ((smaller ((split first second) painter (- n 1)))) (first painter ((second smaller smaller)))))))
(define (split first second) (lambda (painter n) (if (= n 0) painter (let ((smaller ((split first second) painter (- n 1)))) (first painter ((second smaller smaller)))))))