1 /*
2 Copyright (C) 2019 Daniel Schultz
3
4 This file is part of FLINT.
5
6 FLINT is free software: you can redistribute it and/or modify it under
7 the terms of the GNU Lesser General Public License (LGPL) as published
8 by the Free Software Foundation; either version 2.1 of the License, or
9 (at your option) any later version. See <http://www.gnu.org/licenses/>.
10 */
11
12 #include <stdio.h>
13 #include <stdlib.h>
14 #include "fmpz_mod_poly.h"
15
16 int
main(void)17 main(void)
18 {
19 slong i, j;
20 FLINT_TEST_INIT(state);
21
22 flint_printf("find_distinct_nonzero_roots....");
23 fflush(stdout);
24
25 for (i = 0; i < 200 * flint_test_multiplier(); i++)
26 {
27 int highdegreefactor;
28 fmpz_mod_poly_t a, b, r;
29 fmpz_t p, e, zero;
30
31 fmpz_init(zero);
32 fmpz_init_set_ui(p, n_randtest_prime(state, 1));
33 fmpz_init(e);
34 fmpz_mod_poly_init(a, p);
35 fmpz_mod_poly_init(b, p);
36 fmpz_mod_poly_init(r, p);
37
38 fmpz_mod_poly_set_ui(a, 1 + n_randint(state, fmpz_get_ui(p) - 1));
39 highdegreefactor = 0;
40 for (j = n_randint(state, 10); j >= 0; j--)
41 {
42 if (n_randint(state, 10) > 1)
43 {
44 fmpz_mod_poly_randtest_monic_irreducible(b, state, 1);
45 }
46 else
47 {
48 highdegreefactor = 1;
49 fmpz_mod_poly_randtest_monic_irreducible(b, state, 2 + n_randint(state, 9));
50 }
51 fmpz_mod_poly_mul(a, a, b);
52 }
53
54 fmpz_mod_poly_fit_length(r, fmpz_mod_poly_degree(a));
55 if (fmpz_mod_poly_find_distinct_nonzero_roots(r->coeffs, a))
56 {
57 /* check that a is square free */
58 fmpz_mod_poly_derivative(b, a);
59 fmpz_mod_poly_gcd(b, b, a);
60 if (fmpz_mod_poly_degree(b) > 0)
61 {
62 flint_printf("FAIL\ncheck multiple roots i = %wd\n", i);
63 flint_abort();
64 }
65
66 /* check that each root is a root */
67 for (j = fmpz_mod_poly_degree(a) - 1; j >= 0; j--)
68 {
69 if (fmpz_is_zero(r->coeffs + j))
70 {
71 flint_printf("FAIL\ncheck zero root i = %wd\n", i);
72 flint_abort();
73 }
74 if (fmpz_mod_poly_evaluate_fmpz(e, a, r->coeffs + j), !fmpz_is_zero(e))
75 {
76 flint_printf("FAIL\ncheck root is a root i = %wd\n", i);
77 flint_abort();
78 }
79 }
80 }
81 else
82 {
83 fmpz_mod_poly_derivative(b, a);
84 fmpz_mod_poly_gcd(b, b, a);
85 if (!highdegreefactor
86 && fmpz_mod_poly_degree(b) == 0
87 && (fmpz_mod_poly_evaluate_fmpz(e, a, zero), !fmpz_is_zero(e)))
88 {
89 flint_printf("FAIL\ncheck fail return i = %wd\n", i);
90 flint_abort();
91 }
92 }
93
94 fmpz_mod_poly_clear(a);
95 fmpz_mod_poly_clear(b);
96 fmpz_mod_poly_clear(r);
97 fmpz_clear(p);
98 fmpz_clear(e);
99 fmpz_clear(zero);
100 }
101
102 FLINT_TEST_CLEANUP(state);
103
104 flint_printf("PASS\n");
105 return 0;
106 }
107