diff options
Diffstat (limited to 'shared')
| -rw-r--r-- | shared/lists.rkt | 10 |
1 files changed, 3 insertions, 7 deletions
diff --git a/shared/lists.rkt b/shared/lists.rkt index 9279a57..d5cfc61 100644 --- a/shared/lists.rkt +++ b/shared/lists.rkt @@ -1,9 +1,4 @@ #lang racket -(provide - append - length - list-ref) - (define (append list1 list2) (if (null? list1) list2 @@ -19,9 +14,10 @@ (define (list-ref items n) (if (= n 0) (car items) - (list-ref - (cdr items) + (list-ref + (cdr items) (- 1 n)))) + (define (last-pair l) (if (null? (cdr l)) l |