38 lines
798 B
Scheme
38 lines
798 B
Scheme
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(import (chicken string))
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(import (chicken format))
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(import (chicken io))
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(import (chicken sort))
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(import srfi-141)
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(define numbers (map string->number (string-split (read-line) ",")))
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; PART 1
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(define sorted (sort numbers <))
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(define median (list-ref sorted (floor/ (length numbers) 2)))
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(define (part1)
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(foldl
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(lambda (x y) (+ x (abs (- y median))))
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0
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numbers))
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; PART 2
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(define (triangular n) (/ (* n (+ n 1)) 2))
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(define (part2- avg)
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(foldl
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(lambda (x y) (+ x (triangular (abs (- y avg)))))
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0
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numbers))
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(define avgCeil (ceiling/ (foldl + 0 numbers) (length numbers)))
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(define avgFloor (floor/ (foldl + 0 numbers) (length numbers)))
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(define (part2)
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(min (part2- avgCeil) (part2- avgFloor)))
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(format #t "part 1: ~A~%" (part1))
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(format #t "part 2: ~A~%" (part2))
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