blob: e4b17352bfa459545fccee01f78a4ff7e38967dc (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
|
#lang racket
(require sicp)
(define (append list1 list2)
(if (null? list1)
list2
(cons (car list1) (append (cdr list1) list2))))
(define (length items)
(define (length-iter a c)
(if (null? a)
c
(length-iter (cdr a) (inc c))))
(length-iter items 0))
(define (list-ref items n)
(if (= n 0)
(car items)
(list-ref
(cdr items)
(dec n))))
(define (last-pair l)
(if (null? (cdr l))
l
(last-pair (cdr l))))
(define (print-list)
(define odds (list 1 3 5 7 9 11))
(println odds)
(println (list-ref odds 2))
(println (length odds))
(println (append odds (list 22)))
(println (last-pair odds)))
(print-list)
|
