关于list

xiaoliu

有一个list :                 (                 ( 1 a ) ( 2 b ) ( 3 c) ( 4 d ) (5        e ))         ,如何将它变为


( (1 e) ( 2 d) (3 c ) (        4 b) (5 a))                         就是把他的每一项的第二项reverse一下,如何实现,


我的程序里的list 有360项,大家说一个方法,不止限于5项

龙龙仔

(setq LST '((1 A) (2 B) (3 C) (4 D) (5 E)))
(setq LST (reverse LST))
(setq LEN (1+ (length LST)))
(mapcar '(lambda (X)
(list (- LEN (car X)) (cadr X))
)
LST
)

ll_j

(defun rev(alist / blist)
(setq blist (reverse alist))
(mapcar
'(lambda(x y)
(list (car x) (cadr y))
)
alist
blist
)
)

meflying

再简一下... (defun rev(alist / )
(mapcar
'(lambda(x y)
(list (car x) (cadr y))
)
alist
(reverse alist))
)

无痕

(mapcar 'list (mapcar 'car lst)(mapcar 'cadr (reverse lst)))