30 lines
690 B
Scheme
30 lines
690 B
Scheme
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;;; FIBC -- FIB using first-class continuations, written by Kent Dybvig
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(define (_1+ n) (+ n 1))
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(define (_1- n) (- n 1))
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;;; fib with peano arithmetic (using numbers) with call/cc
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(define (addc x y k)
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(if (zero? y)
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(k x)
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(addc (_1+ x) (_1- y) k)))
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(define (fibc x c)
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(if (zero? x)
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(c 0)
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(if (zero? (_1- x))
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(c 1)
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(addc (call-with-current-continuation (lambda (c) (fibc (_1- x) c)))
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(call-with-current-continuation (lambda (c) (fibc (_1- (_1- x)) c)))
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c))))
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(define (main)
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(run-benchmark
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"fibc"
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fibc-iters
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(lambda (result) (equal? result 2584))
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(lambda (x c) (lambda () (fibc x c)))
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18
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(lambda (n) n)))
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