Created
August 20, 2012 04:45
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traverse a list recursively and find specific elements
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(defun traverse (lst elt) | |
(defun traverse-and-count (lst elt cnt) | |
(if (= 0 (length lst)) | |
cnt | |
(progn | |
(if (equal elt (car lst)) | |
(traverse-and-count (cdr lst) elt (+ 1 cnt)) | |
(traverse-and-count (cdr lst) elt cnt))))) | |
(traverse-and-count lst elt 0)) | |
(traverse '(1 3 4 5 6 1 4 1) 1) ;; 3 | |
(traverse '("a" "b" 2 5 "b" 8 0) "b") ;; 2 |
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