aa9bc17601
BMakefiles and other bits will follow. Requested by: Andrey Chernov Made world by: Chuck Robey
65 lines
1.6 KiB
C
65 lines
1.6 KiB
C
/* mpz_gcd_ui -- Calculate the greatest common divisior of two integers.
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Copyright (C) 1994, 1996 Free Software Foundation, Inc.
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This file is part of the GNU MP Library.
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The GNU MP Library is free software; you can redistribute it and/or modify
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it under the terms of the GNU Library General Public License as published by
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the Free Software Foundation; either version 2 of the License, or (at your
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option) any later version.
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The GNU MP Library is distributed in the hope that it will be useful, but
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WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
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or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public
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License for more details.
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You should have received a copy of the GNU Library General Public License
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along with the GNU MP Library; see the file COPYING.LIB. If not, write to
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the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
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MA 02111-1307, USA. */
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#include "gmp.h"
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#include "gmp-impl.h"
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unsigned long int
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#if __STDC__
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mpz_gcd_ui (mpz_ptr w, mpz_srcptr u, unsigned long int v)
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#else
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mpz_gcd_ui (w, u, v)
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mpz_ptr w;
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mpz_srcptr u;
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unsigned long int v;
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#endif
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{
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mp_size_t size;
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mp_limb_t res;
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size = ABS (u->_mp_size);
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if (size == 0)
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res = v;
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else if (v == 0)
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{
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if (w != NULL && u != w)
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{
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if (w->_mp_alloc < size)
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_mpz_realloc (w, size);
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MPN_COPY (w->_mp_d, u->_mp_d, size);
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}
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w->_mp_size = size;
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/* We can't return any useful result for gcd(big,0). */
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return size > 1 ? 0 : w->_mp_d[0];
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}
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else
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res = mpn_gcd_1 (u->_mp_d, size, v);
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if (w != NULL)
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{
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w->_mp_d[0] = res;
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w->_mp_size = 1;
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}
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return res;
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}
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