car and cdr in Scheme are driving me crazy ...

Posted by kristian Roger on Stack Overflow See other posts from Stack Overflow or by kristian Roger
Published on 2010-04-30T20:44:38Z Indexed on 2010/04/30 20:57 UTC
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Hi Im facing a problem with the car and cdr functions

for example:

first I defined a list called it x

(define x (a (bc) d ( (ef) g ) ))

so x now is equal to (a (bc) d ( (ef) g ) )

now for example I need to get the g from this list using only car and cdr (!! noshortcuts as caddr cddr !!) the correct answer is:

(car(cdr(car(cdr(cdr(cdr x))))))

BUT how ? :-( I work according to the rules (the car gives the head of list and cdr gives the tail)

and instead of getting the answer above I keep reaching wrong answers. Can any one help me in understanding this ... give me step or a way to solve it step by step

Thanks in advance. I'm really sick of Scheme.

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