I recently came across a lecture on DFA. I tried to use it to determine whether a given 'search string' is found in the 'input string'. Please tell me if there is a better way
(display "Enter input string")
(define input-str (read-line (current-input-port)))
(display "Enter Search String")
(define search-str (read-line (current-input-port)))
(define (search-match in-str sr-str)
(let* ((in-str-len (string-length in-str))
(start-state 0)
(end-state (string-length sr-str)))
(letrec ((iter (lambda (i curr-state)
(cond ((= curr-state end-state) #t)
((= i in-str-len) #f)
((equal? (string-ref in-str i)
(string-ref sr-str curr-state))
(iter (+ i 1) (+ curr-state 1)))
(else
(iter (+ i 1) start-state))))))
(iter 0 0))))
(search-match input-str search-str)
