22 lines
380 B
Scheme
22 lines
380 B
Scheme
#lang scheme
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(require 2htdp/universe 2htdp/image)
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(define (slow)
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(let sloop ([n (expt 2 22)])
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(unless (zero? n)
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(sloop (- n 1)))))
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(define (update-world w)
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(slow)
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(- w 1))
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(define (render w)
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(circle 30 'solid (if (odd? w) 'red 'green)))
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(big-bang 10
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(on-tick update-world)
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(on-draw render)
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(stop-when zero?))
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(printf "done\n")
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