142 lines
3.9 KiB
C
142 lines
3.9 KiB
C
/*=============================================================================
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This file is part of FLINT.
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FLINT is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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FLINT is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with FLINT; if not, write to the Free Software
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Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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=============================================================================*/
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/******************************************************************************
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Copyright (C) 2011 Sebastian Pancratz
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******************************************************************************/
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#include <stdio.h>
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#include <stdlib.h>
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#include <gmp.h>
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#include "flint.h"
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#include "fmpz.h"
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#include "ulong_extras.h"
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int main(void)
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{
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int i, result;
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FLINT_TEST_INIT(state);
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flint_printf("sqrtmod....");
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fflush(stdout);
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for (i = 0; i < 100 * flint_test_multiplier(); i++) /* Test random integers */
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{
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int ans;
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fmpz_t a, b, c, p;
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mp_limb_t prime;
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prime = n_randint(state, UWORD(1) << (FLINT_BITS - 1));
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prime = n_nextprime(prime, 1);
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fmpz_init(a);
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fmpz_init(b);
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fmpz_init(c);
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fmpz_init(p);
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fmpz_set_ui(p, prime);
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fmpz_randm(a, state, p);
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ans = fmpz_sqrtmod(b, a, p);
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fmpz_mul(c, b, b);
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fmpz_mod(c, c, p);
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result = (ans == 0 || fmpz_equal(a, c));
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if (!result)
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{
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flint_printf("FAIL (random):\n");
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flint_printf("p = "), fmpz_print(p), flint_printf("\n");
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flint_printf("a = "), fmpz_print(a), flint_printf("\n");
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flint_printf("b = "), fmpz_print(b), flint_printf("\n");
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flint_printf("c = "), fmpz_print(c), flint_printf("\n");
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abort();
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}
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fmpz_clear(a);
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fmpz_clear(b);
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fmpz_clear(c);
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fmpz_clear(p);
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}
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for (i = 0; i < 100 * flint_test_multiplier(); i++) /* Test random squares */
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{
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int ans;
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fmpz_t a, b, c, d, p;
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mp_limb_t prime;
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prime = n_randint(state, UWORD(1) << (FLINT_BITS - 1));
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prime = n_nextprime(prime, 1);
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fmpz_init(a);
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fmpz_init(b);
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fmpz_init(c);
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fmpz_init(d);
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fmpz_init(p);
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fmpz_set_ui(p, prime);
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do
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fmpz_randm(b, state, p);
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while (fmpz_is_zero(b));
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fmpz_mul(a, b, b);
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fmpz_mod(a, a, p);
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/* check a special case */
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if (i == 0)
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{
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fmpz_set_str(p, "15951355998396157", 10);
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fmpz_set_str(a, "7009303413761286", 10);
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}
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ans = fmpz_sqrtmod(c, a, p);
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fmpz_mul(d, c, c);
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fmpz_mod(d, d, p);
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result = (ans && fmpz_equal(a, d));
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if (!result)
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{
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flint_printf("FAIL (squares):\n");
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flint_printf("p = "), fmpz_print(p), flint_printf("\n");
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flint_printf("a (= b^2) = "), fmpz_print(a), flint_printf("\n");
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flint_printf("b = "), fmpz_print(b), flint_printf("\n");
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flint_printf("c (= sqrt(a) = "), fmpz_print(c), flint_printf("\n");
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flint_printf("d (= c^2) = "), fmpz_print(d), flint_printf("\n");
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flint_printf("ans = %d\n", ans);
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abort();
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}
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fmpz_clear(a);
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fmpz_clear(b);
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fmpz_clear(c);
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fmpz_clear(d);
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fmpz_clear(p);
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}
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FLINT_TEST_CLEANUP(state);
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flint_printf("PASS\n");
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return 0;
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}
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