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(use-modules (srfi srfi-1)
(srfi srfi-42))
(define (products min max)
(list-ec (:range x min max) (:range y min max) (* x y)))
(define (palindrome? x)
(define (test s)
(cond ((or (string-null? s)
(= (string-length s) 1))
#t)
((equal? (string-ref s 0)
(string-ref s (1- (string-length s))))
(test (substring s 1 (1- (string-length s)))))
(else
#f)))
(let ((s (number->string x)))
(test s)))
(define (palindrome-products min max)
(filter palindrome? (products min max)))
(reduce max 0 (palindrome-products 100 1000))
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