39 lines
769 B
C
39 lines
769 B
C
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/* LibTomPoly, Polynomial Basis Math -- Tom St Denis
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*
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* LibTomPoly is a public domain library that provides
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* polynomial basis arithmetic support. It relies on
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* LibTomMath for large integer support.
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*
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* This library is free for all purposes without any
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* express guarantee that it works.
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*
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* Tom St Denis, tomstdenis@iahu.ca, http://poly.libtomcrypt.org
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*/
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#include <tompoly.h>
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int pb_rshd(pb_poly *a, int x)
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{
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int y;
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if (x >= a->used) {
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pb_zero(a);
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return MP_OKAY;
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}
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if (x <= 0) {
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return MP_OKAY;
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}
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for (y = x; y < a->used; y++) {
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mp_exch(&(a->terms[y]), &(a->terms[y-x]));
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}
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for (y = a->used - x; y < a->used; y++) {
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mp_zero(&(a->terms[y]));
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}
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a->used -= x;
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return MP_OKAY;
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}
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