(define (middle3 x)
    (if (even? (length x))
        (println "You entered " x ". I need an odd number of digits, not " (length x) ".")
        (if (< (length x) 3)
            (println "You entered " x ". Sorry, but I need 3 or more digits.")
            (println "The middle 3 digits of " x " are " ((- (/ (- (length x) 1) 2) 1) 3 (string (abs x))) ".")
        )
    )
)

(map middle3 lst)