7 lines
279 B
Scheme
7 lines
279 B
Scheme
(define (dec31wd year)
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(remainder (apply + (map (lambda (d) (quotient year d)) '(1 4 -100 400))) 7))
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(define (long? year) (or (= 4 (dec31wd year)) (= 3 (dec31wd (- year 1)))))
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(display "Long years between 1800 and 2100:") (newline)
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(display (filter long? (iota 300 1800)))
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