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/*
Copyright (C) 2018 Daniel Schultz
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 "mpoly.h"
/* this file does not need to change with new orderings */
/* try to prove A is not a square */
int mpoly_is_proved_not_square(
const ulong * Aexps,
slong Alen,
flint_bitcnt_t Abits,
slong N,
ulong * t) /* temp of size N */
{
slong i;
if (Alen < 1)
return 0;
/* check for odd degrees & check total degree too in degree orderings */
mpoly_monomial_set(t, Aexps + N*0, N);
if (Abits <= FLINT_BITS)
{
ulong mask = mpoly_overflow_mask_sp(Abits);
for (i = 1; i < Alen; i++)
mpoly_monomial_max(t, t, Aexps + N*i, Abits, N, mask);
return !mpoly_monomial_halves(t, t, N, mask);
}
else
{
for (i = 1; i < Alen; i++)
mpoly_monomial_max_mp(t, t, Aexps + N*i, Abits, N);
return !mpoly_monomial_halves_mp(t, t, N, Abits);
}
}