1/* Exercise mpz_primorial_ui.
2
3Copyright 2000-2002, 2012, 2015 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 <stdio.h>
21#include <stdlib.h>
22#include "gmp-impl.h"
23#include "tests.h"
24
25
26/* Usage: t-primorial_ui [x|num]
27
28   With no arguments testing goes up to the initial value of "limit" below.
29   With a number argument tests are carried that far, or with a literal "x"
30   tests are continued without limit (this being meant only for development
31   purposes).  */
32
33static int isprime (unsigned long int t);
34
35int
36main (int argc, char *argv[])
37{
38  unsigned long  n;
39  unsigned long  limit = 2222;
40  gmp_randstate_ptr rands;
41  mpz_t          f, r, bs;
42
43  tests_start ();
44  rands = RANDS;
45
46  if (argc > 1 && argv[1][0] == 'x')
47    limit = ULONG_MAX;
48  else
49    TESTS_REPS (limit, argv, argc);
50
51  /* for small limb testing */
52  limit = MIN (limit, MP_LIMB_T_MAX);
53
54  mpz_init_set_ui (f, 1);  /* 0# = 1 */
55  mpz_init (r);
56
57  n = 0;
58  do
59    {
60      mpz_primorial_ui (r, n);
61      MPZ_CHECK_FORMAT (r);
62
63      if (mpz_cmp (f, r) != 0)
64	{
65	  printf ("mpz_primorial_ui(%lu) wrong\n", n);
66	  printf ("  got  "); mpz_out_str (stdout, 10, r); printf("\n");
67	  printf ("  want "); mpz_out_str (stdout, 10, f); printf("\n");
68	  abort ();
69	}
70
71      if (isprime (++n))
72	mpz_mul_ui (f, f, n);  /* p# = (p-1)# * (p) */
73      if (n%16 == 0) { mpz_clear (r); mpz_init (r); }
74    } while (n < limit);
75
76  n = 0; limit =1;
77  mpz_init (bs);
78  do
79    {
80      unsigned long i, d;
81
82      mpz_urandomb (bs, rands, 21);
83      i = mpz_get_ui (bs);
84      mpz_urandomb (bs, rands, 9);
85      d = mpz_get_ui (bs) + 3*64;
86      mpz_primorial_ui (f, i);
87      MPZ_CHECK_FORMAT (f);
88      mpz_primorial_ui (r, i+d);
89      MPZ_CHECK_FORMAT (r);
90
91      do {
92	if (isprime (++i))
93	  mpz_mul_ui (f, f, i);
94      } while (--d != 0);
95
96      if (mpz_cmp (f, r) != 0)
97	{
98	  printf ("mpz_primorial_ui(%lu) wrong\n", i);
99	  printf ("  got  "); mpz_out_str (stdout, 10, r); printf("\n");
100	  printf ("  want "); mpz_out_str (stdout, 10, f); printf("\n");
101	  abort ();
102	}
103    } while (++n < limit);
104  /* Chech a single "big" value, modulo a larger prime */
105  n = 2095637;
106  mpz_primorial_ui (r, n);
107  mpz_set_ui (f, 13);
108  mpz_setbit (f, 64); /* f = 2^64 + 13 */
109  mpz_tdiv_r (r, r, f);
110  mpz_set_str (f, "BAFCBF3C95B217D5", 16);
111
112  if (mpz_cmp (f, r) != 0)
113    {
114      printf ("mpz_primorial_ui(%lu) wrong\n", n);
115      printf ("  got  "); mpz_out_str (stdout, 10, r); printf("\n");
116      printf ("  want "); mpz_out_str (stdout, 10, f); printf("\n");
117      abort ();
118    }
119
120  mpz_clear (bs);
121  mpz_clear (f);
122  mpz_clear (r);
123
124  tests_end ();
125
126  exit (0);
127}
128
129static int
130isprime (unsigned long int t)
131{
132  unsigned long int q, r, d;
133
134  if (t < 3 || (t & 1) == 0)
135    return t == 2;
136
137  for (d = 3, r = 1; r != 0; d += 2)
138    {
139      q = t / d;
140      r = t - q * d;
141      if (q < d)
142	return 1;
143    }
144  return 0;
145}
146