Get last element of a list

[daimous]

Hi Guys! help please..How can i get the last element of a list with a list? say i have a list

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((4 5 6) (d e f) (h i j) (5 5 5 5)) )

how can i have the last element so that my out put would be

(6 f j 5)

Thanks in advance!

[nuntius]

Treasure hunt: You can use two functions from the following lists.
(apropos "last" :cl)
(apropos "map" :cl)

More details can be found in the HyperSpec. A good search tool is at
http://lispdoc.com/

Or see the quick reference at
http://clqr.berlios.de/

[Wolfgang Tsafack]

@daimous

You need to use mapcar in combination wiht the lambda-function. it's the best way to solve your problem!

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(defun getAllLastElems(listOfLists)
     (mapcar (lambda (list-elem)
                        (last list-elem)
                  ) listOfLists)
)

just try it. I don't know if the function (last list) is correct. If it isn't, try to found a function that return you the last
element of a simple list and replace it with the function last in this code (with the same argument. Don't change the name [list-elem]!)

[nuntius]

or simply

Code: Select all

(mapcan #'last '((4 5 6) (d e f) (h i j) (5 5 5 5)))

[methusala]

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(defun mylast(x)
       (if (and (listp x) (null (cdr x)) ) (car x)
       (mylast (cdr x))))

(defun eachlast(x)
        (if (null x) x
	    (progn      
 	    (cons (mylast (car x))
       	    (eachlast (cdr x))))))

CL-USER> (eachlast '((1 9 5)(3 3 3)(1 0 3 0 2)))
(5 3 2)

[Wolfgang Tsafack]

(defun getAllLastElems(listOfLists)
(mapcar (lambda (list-elem)
(last list-elem)
) listOfLists)
)

Hello, I make an error when writing this last post. The function last return a list not a value

Code: Select all

(last '(a d 6)) --> (6)

So you have to add first/or car into the lambda-function. So the correct code is show below:

(defun getAllLastElems(listOfLists)
(mapcar (lambda (list-elem)
(car (last list-elem))
) listOfLists)
)

That work effiziently.

@methusala
That was also a good idea solving the problem. But too long for me.

all have a good day