Topic: Mapcar and lambda manipulation

[Jim2018]

I want to add, using mapcar and lambda, to the elements of a list ((X1 Y1) (X2 Y2) .... (Xn Yn)) a string type element that will count the members of the list, starting from (one) 1 and will have the form (("1" X1 Y1) ("2" X2 Y2) .... ("n" Xn Yn)).
The only I have managed is to create a list (" " X1 Y1) (" " X2 Y2) .... (" " Xn Yn)) with the following order  (mapcar '(lambda (x) (cons " ")) e_list)
Any help accepted

[baitang36]

Code - Auto/Visual Lisp: [Select]

1. (setq e_list '( (1 1) (2 2) (3 3) (4 4)))
2. (setq y 0)
3. (mapcar '(lambda (x)
4.            (setq y (+ 1 y ) )
5.            (cons   (itoa y) x)
6.          )
7.         e_list
8. )

it return (("1" 1 1) ("2" 2 2) ("3" 3 3) ("4" 4 4))

[Jim2018]

Thank you!!!