46 lines
1005 B
C
46 lines
1005 B
C
/* LibTomMath, multiple-precision integer library -- Tom St Denis
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*
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* LibTomMath is library that provides for multiple-precision
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* integer arithmetic as well as number theoretic functionality.
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*
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* The library is designed directly after the MPI library by
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* Michael Fromberger but has been written from scratch with
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* additional optimizations in place.
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*
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* The library is free for all purposes without any express
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* guarantee it works.
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*
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* Tom St Denis, tomstdenis@iahu.ca, http://libtommath.iahu.ca
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*/
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#include <tommath.h>
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/* shift right a certain amount of digits */
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void
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mp_rshd (mp_int * a, int b)
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{
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int x;
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/* if b <= 0 then ignore it */
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if (b <= 0) {
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return;
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}
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/* if b > used then simply zero it and return */
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if (a->used < b) {
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mp_zero (a);
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return;
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}
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/* shift the digits down */
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for (x = 0; x < (a->used - b); x++) {
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a->dp[x] = a->dp[x + b];
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}
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/* zero the top digits */
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for (; x < a->used; x++) {
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a->dp[x] = 0;
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}
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mp_clamp (a);
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}
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