Integer long division: Difference between revisions
Content added Content deleted
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; ($/ 1 17) => 588235294117647 ; 16 |
; ($/ 1 17) => 588235294117647 ; 16 |
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(assert (and (integerp a) (integerp b) (not (zerop b)))) |
(assert (and (integerp a) (integerp b) (not (zerop b)))) |
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(do* (c |
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(i0 (1+ (max (factor-multiplicity b 2) (factor-multiplicity b 5)))) ; the position which marks the beginning of the period |
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(r a (* 10 r)) ; remainder |
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(r a (* 10 r)) ; remainder |
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(i 0 (1+ i)) ; iterations counter |
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(rem (if (= i i0) r -1) (if (= i i0) r rem)) ) ; the first remainder against which to check for repeating remainders |
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(( |
(rem (if (= i i0) r -1) (if (= i i0) r rem)) ) ; the first remainder against which to check for repeating remainders |
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((and (= r rem) (not (= i i0))) (- i i0)) |
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(multiple-value-setq (c r) (floor r b)) |
(multiple-value-setq (c r) (floor r b)) |
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(princ c) )) |
(princ c) )) |
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; (factor-multiplicity 12 2) => 2 |
; (factor-multiplicity 12 2) => 2 |
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(do* ((i 0 (1+ i)) |
(do* ((i 0 (1+ i)) |
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(n (/ n factor) (/ n factor)) ) |
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((not (integerp n)) i) |
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() )) |
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</lang> |
</lang> |
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