Created
July 13, 2022 16:42
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(define (run-length s) | |
(letrec ((run-length-h (lambda (s vec count prev-char) | |
(if (null? s) | |
(vector-append vec (vector `(,prev-char ,count))) | |
(let ((c (car s))) | |
(if (char=? prev-char c) | |
(run-length-h (cdr s) vec (+ count 1) prev-char) | |
(if (char=? prev-char #\null) | |
(run-length-h (cdr s) vec 1 c) | |
(run-length-h (cdr s) (vector-append vec (vector `(,prev-char ,count))) 1 c)))))))) | |
(run-length-h s '#() 0 #\null))) |
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