18 lines
527 B
Scheme
18 lines
527 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 srfi-14)
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(import srfi-60)
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(define (add-lines l r)
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(map (lambda (l r) (+ l (- (char->integer r) 48))) l r))
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(define lines (map string->list (read-lines)))
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(define counts (foldl add-lines (map (lambda (_) 0) (car lines)) lines))
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(define hl (/ (length lines) 2))
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(define gamma (list->integer (map (lambda (x) (> x hl)) counts)))
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(define epsilon (list->integer (map (lambda (x) (< x hl)) counts)))
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(format #t "part 1: ~A~%" (* gamma epsilon))
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