1 /* mpz_gcdext(g, s, t, a, b) -- Set G to gcd(a, b), and S and T such that
4 Copyright (C) 1991 Free Software Foundation, Inc.
6 This file is part of the GNU MP Library.
8 The GNU MP Library is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2, or (at your option)
13 The GNU MP Library is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with the GNU MP Library; see the file COPYING. If not, write to
20 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
29 mpz_gcdext (MP_INT *g, MP_INT *s, MP_INT *t, const MP_INT *a, const MP_INT *b)
31 mpz_gcdext (g, s, t, a, b)
39 MP_INT s0, s1, q, r, x, d0, d1;
41 mpz_init_set_ui (&s0, 1);
42 mpz_init_set_ui (&s1, 0);
46 mpz_init_set (&d0, a);
47 mpz_init_set (&d1, b);
51 mpz_divmod (&q, &r, &d0, &d1);
55 mpz_mul (&x, &s1, &q);
56 mpz_sub (&x, &s0, &x);
64 mpz_sub (&x, &d0, &x);