sicp 习题2.17

Welcome to DrRacket, version 5.3.3 [3m].
Language: planet neil/sicp; memory limit: 128 MB.
> (define a (list 1 2 3 4 5))
> (last-pair a)
(mcons 5 '())
> 

运行:

Welcome to DrRacket, version 5.3.3 [3m].
Language: planet neil/sicp; memory limit: 128 MB.
> (define a (list 1 2 3 4 5))
> (last-pair a)
(mcons 5 '())
>