S-99-18 Extract a slice from a list.
Given two indices, I and K, the slice is the list containing the elements between the I'th and K'th element of the original list (both limits included). Start counting the elements with 1.
(slice '(a b c d e f g h i k) 3 7) ; => (c d e f g)
(define (take xs n) (if (or (zero? n) (null? xs)) '() (cons (car xs) (take (cdr xs) (- n 1))))) (define (slice xs start end) (cond ((null? xs) '()) ((> start 1) (slice (cdr xs) (- start 1) (- end 1))) (else (take xs end))))