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/*
Copyright (C) 2020 Fredrik Johansson
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"
#include "qqbar.h"
int
qqbar_acos_pi(slong * p, ulong * q, const qqbar_t x)
{
if (qqbar_asin_pi(p, q, x))
{
slong a, b, g;
a = *p;
b = *q;
/* 1/2 - a/b */
a = b - 2 * a;
b = 2 * b;
g = n_gcd(FLINT_ABS(a), b);
if (g != 1)
{
a /= g;
b /= g;
}
*p = a;
*q = b;
return 1;
}
return 0;
}