[LISP函数-表] 分解复表（炸表）

狂刀

2. 
   
3.   [FONT=courier new]
   
4. 
   
5. ;|from autodesk discussion groups (cad讨论组)---how to covert list
   
6. ;//////////////////////////////////////////////////////////////////////////;
   
7. Now who would like to show how to flatten any nested list
   
8. such as '((1 . 2) (1 2 3) ((1 2) (2 3) 4))
   
9. into '(1 2 1 2 3 1 2 2 3 4)
   
10. ;//////////////////////////////////////////////////////////////////////////;
    
11. |;
    
12. ;方法一:
    
13. (defun flatten (lst)
    
14.   (cond ((null lst) nil)
    
15.         ((atom lst) (list lst))
    
16.         (T (append (flatten (car lst))(flatten (cdr lst))))
    
17. ))
    
18. ;方法二:
    
19. (defun delist ( lst / x )
    
20.   (if lst
    
21.    (if (atom lst)
    
22.        (list lst)
    
23.        (if (atom (setq x (car lst)))
    
24.            (cons x (delist (cdr lst)))
    
25.            (append (delist x) (delist (cdr lst)))
    
26.        )
    
27.    )
    
28.   )
    
29. )
    
30. 
    
31.   [/FONT]
    

<br />   [FONT=courier new]<br /> <br /> ;|from autodesk discussion groups (cad讨论组)---how to covert list <br /> ;//////////////////////////////////////////////////////////////////////////;<br /> Now who would like to show how to flatten any nested list<br /> such as '((1 . 2) (1 2 3) ((1 2) (2 3) 4))<br /> into '(1 2 1 2 3 1 2 2 3 4)<br /> ;//////////////////////////////////////////////////////////////////////////;<br /> |;<br /> ;方法一:<br /> (defun flatten (lst)<br />   (cond ((null lst) nil)<br />         ((atom lst) (list lst))<br />         (T (append (flatten (car lst))(flatten (cdr lst))))<br /> ))<br /> ;方法二:<br /> (defun delist ( lst / x )<br />   (if lst<br />    (if (atom lst)<br />        (list lst)<br />        (if (atom (setq x (car lst)))<br />            (cons x (delist (cdr lst)))<br />            (append (delist x) (delist (cdr lst)))<br />        )<br />    )<br />   )<br /> )<br /> <br />   [/FONT]<br />

aeo

命令: (flatten '(nil 2 3))
==>  (2 3)

狂刀

(flatten '(nil (2 nil 3 (4 nil))));;-> (nil 2 nil 3 4 nil)

2. 
   
3. (defun flatten (lst / a)
   
4.   (cond ((null lst) nil)
   
5.         ((atom lst) (list lst))
   
6.         (T (setq a (flatten (car lst)))(append (if a a '(nil))(flatten (cdr lst))))
   
7. ))
   

<br /> (defun flatten (lst / a)<br />   (cond ((null lst) nil)<br />         ((atom lst) (list lst))<br />         (T (setq a (flatten (car lst)))(append (if a a '(nil))(flatten (cdr lst))))<br /> ))<br />