1/*
2
3Copyright 2012, 2013 Free Software Foundation, Inc.
4
5This file is part of the GNU MP Library test suite.
6
7The GNU MP Library test suite is free software; you can redistribute it
8and/or modify it under the terms of the GNU General Public License as
9published by the Free Software Foundation; either version 3 of the License,
10or (at your option) any later version.
11
12The GNU MP Library test suite is distributed in the hope that it will be
13useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
14MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General
15Public License for more details.
16
17You should have received a copy of the GNU General Public License along with
18the GNU MP Library test suite.  If not, see https://www.gnu.org/licenses/.  */
19
20#include <limits.h>
21#include <stdlib.h>
22#include <stdio.h>
23
24#include "testutils.h"
25
26#define MAXBITS 400
27#define COUNT 10000
28
29/* Called when s is supposed to be floor(root(u,z)), and r = u - s^z */
30static int
31rootrem_valid_p (const mpz_t u, const mpz_t s, const mpz_t r, unsigned long z)
32{
33  mpz_t t;
34
35  mpz_init (t);
36  if (mpz_fits_ulong_p (s))
37    mpz_ui_pow_ui (t, mpz_get_ui (s), z);
38  else
39    mpz_pow_ui (t, s, z);
40  mpz_sub (t, u, t);
41  if ((mpz_sgn (t) != mpz_sgn(u) && mpz_sgn (t) != 0) || mpz_cmp (t, r) != 0)
42    {
43      mpz_clear (t);
44      return 0;
45    }
46  if (mpz_sgn (s) > 0)
47    mpz_add_ui (t, s, 1);
48  else
49    mpz_sub_ui (t, s, 1);
50  mpz_pow_ui (t, t, z);
51  if (mpz_cmpabs (t, u) <= 0)
52    {
53      mpz_clear (t);
54      return 0;
55    }
56
57  mpz_clear (t);
58  return 1;
59}
60
61void
62testmain (int argc, char **argv)
63{
64  unsigned i;
65  unsigned long e;
66  mpz_t u, s, r, bs;
67
68  mpz_init (u);
69  mpz_init (s);
70  mpz_init (r);
71  mpz_init (bs);
72
73  for (i = 0; i < COUNT; i++)
74    {
75      mini_rrandomb (u, MAXBITS);
76      mini_rrandomb (bs, 12);
77      e = mpz_getlimbn (bs, 0) % mpz_sizeinbase (u, 2) + 1;
78      if ((e & 1) && (mpz_getlimbn (bs, 0) & (1L<<10)))
79	mpz_neg (u, u);
80      mpz_rootrem (s, r, u, e);
81
82      if (!rootrem_valid_p (u, s, r, e))
83	{
84	  fprintf (stderr, "mpz_rootrem(%lu-th) failed:\n", e);
85	  dump ("u", u);
86	  dump ("root", s);
87	  dump ("rem", r);
88	  abort ();
89	}
90    }
91  mpz_clear (bs);
92  mpz_clear (u);
93  mpz_clear (s);
94  mpz_clear (r);
95}
96