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/*
Copyright (C) 2008 Peter Shrimpton
Copyright (C) 2009 William Hart
Copyright (C) 2014 Dana Jacobsen
This file is part of FLINT.
FLINT is free software: you can redistribute it and/or modify it under
the terms of the GNU Lesser General Public License (LGPL) as published
by the Free Software Foundation; either version 3 of the License, or
(at your option) any later version. See <https://www.gnu.org/licenses/>.
*/
#include "ulong_extras.h"
int
n_is_strong_probabprime_precomp(ulong n, double npre, ulong a,
ulong d)
{
ulong t = d;
ulong y;
/* Map large base to range 2 ... n - 1 */
if (a >= n)
a = n_mod2_precomp(a, n, npre);
if ((a <= 1) || (a == n-1)) return 1;
y = n_powmod_ui_precomp(a, t, n, npre);
if (y == UWORD(1))
return 1;
t <<= 1;
while ((t != n - 1) && (y != n - 1))
{
y = n_mulmod_precomp(y, y, n, npre);
t <<= 1;
}
return (y == n - 1);
}