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Annotation of OpenXM/src/kan96xx/gmp-2.0.2/mpz/gcd_ui.c, Revision 1.1

1.1     ! maekawa     1: /* mpz_gcd_ui -- Calculate the greatest common divisior of two integers.
        !             2:
        !             3: Copyright (C) 1994, 1996 Free Software Foundation, Inc.
        !             4:
        !             5: This file is part of the GNU MP Library.
        !             6:
        !             7: The GNU MP Library is free software; you can redistribute it and/or modify
        !             8: it under the terms of the GNU Library General Public License as published by
        !             9: the Free Software Foundation; either version 2 of the License, or (at your
        !            10: option) any later version.
        !            11:
        !            12: The GNU MP Library is distributed in the hope that it will be useful, but
        !            13: WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
        !            14: or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Library General Public
        !            15: License for more details.
        !            16:
        !            17: You should have received a copy of the GNU Library General Public License
        !            18: along with the GNU MP Library; see the file COPYING.LIB.  If not, write to
        !            19: the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
        !            20: MA 02111-1307, USA. */
        !            21:
        !            22: #include "gmp.h"
        !            23: #include "gmp-impl.h"
        !            24:
        !            25: unsigned long int
        !            26: #if __STDC__
        !            27: mpz_gcd_ui (mpz_ptr w, mpz_srcptr u, unsigned long int v)
        !            28: #else
        !            29: mpz_gcd_ui (w, u, v)
        !            30:      mpz_ptr w;
        !            31:      mpz_srcptr u;
        !            32:      unsigned long int v;
        !            33: #endif
        !            34: {
        !            35:   mp_size_t size;
        !            36:   mp_limb_t res;
        !            37:
        !            38:   size = ABS (u->_mp_size);
        !            39:
        !            40:   if (size == 0)
        !            41:     res = v;
        !            42:   else if (v == 0)
        !            43:     {
        !            44:       if (w != NULL && u != w)
        !            45:        {
        !            46:          if (w->_mp_alloc < size)
        !            47:            _mpz_realloc (w, size);
        !            48:
        !            49:          MPN_COPY (w->_mp_d, u->_mp_d, size);
        !            50:        }
        !            51:       w->_mp_size = size;
        !            52:       /* We can't return any useful result for gcd(big,0).  */
        !            53:       return size > 1 ? 0 : w->_mp_d[0];
        !            54:     }
        !            55:   else
        !            56:     res = mpn_gcd_1 (u->_mp_d, size, v);
        !            57:
        !            58:   if (w != NULL)
        !            59:     {
        !            60:       w->_mp_d[0] = res;
        !            61:       w->_mp_size = 1;
        !            62:     }
        !            63:   return res;
        !            64: }