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/*
Copyright (C) 2013 Mike Hansen
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 "fq_zech.h"
void
fq_zech_pth_root(fq_zech_t rop, const fq_zech_t op1, const fq_zech_ctx_t ctx)
{
slong i, d;
ulong e;
double qm1inv;
if (fq_zech_is_zero(op1, ctx) || fq_zech_is_one(op1, ctx))
{
rop->value = op1->value;
return;
}
d = fq_zech_ctx_degree(ctx) - 1;
qm1inv = n_precompute_inverse(ctx->qm1);
e = op1->value;
for (i = 0; i < d; i++)
{
e = n_mulmod_precomp(ctx->p, e, ctx->qm1, qm1inv);
}
rop->value = e;
}