24 lines
687 B
Racket
24 lines
687 B
Racket
#lang racket/base
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(require racket/cmdline)
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(define (generate receive-ch n)
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(if (zero? n)
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receive-ch
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(let ([ch (make-channel)])
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(thread (lambda ()
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(let loop ()
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(channel-put ch (add1 (channel-get receive-ch)))
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(loop))))
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(generate ch (sub1 n)))))
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(let ([n (command-line #:args (n) (string->number n))])
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(let* ([start-ch (make-channel)]
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[end-ch (generate start-ch 500)])
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(let loop ([n n][total 0])
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(if (zero? n)
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(printf "~a\n" total)
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(begin
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(channel-put start-ch 0)
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(loop (sub1 n)
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(+ total (channel-get end-ch))))))))
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