40 lines
929 B
Scheme
40 lines
929 B
Scheme
; -*- scheme -*-
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(define (rule30-step b)
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(let ((L (ash b -1))
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(R (ash b 1)))
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(let ((~b (lognot b))
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(~L (lognot L))
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(~R (lognot R)))
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(logior (logand L ~b ~R)
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(logand ~L b R)
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(logand ~L b ~R)
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(logand ~L ~b R)))))
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(define (nestlist f zero n)
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(if (<= n 0) ()
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(cons zero (nestlist f (f zero) (- n 1)))))
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(define (make-string k ch)
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(cond ((<= k 0) "")
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((= k 1) (string ch))
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((= k 2) (string ch ch))
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((odd? k) (string ch (make-string (- k 1) ch)))
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(else (let ((half (make-string (/ k 2) ch)))
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(string half half)))))
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(define (pad0 s n) (string (make-string (- n (length s)) "0") s))
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(define (bin-draw s)
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(string.map (lambda (c) (case c
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(#\1 #\#)
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(#\0 #\ )
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(else c)))
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s))
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(for-each (lambda (n)
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(begin
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(princ (bin-draw (pad0 (number->string n 2) 63)))
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(terpri)))
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(nestlist rule30-step (uint64 0x0000000080000000) 32))
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