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/*=============================================================================
This file is part of FLINT.
FLINT is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
FLINT is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with FLINT; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
=============================================================================*/
/******************************************************************************
Copyright (C) 2009 Thomas Boothby
Copyright (C) 2009 William Hart
******************************************************************************/
#include <gmp.h>
#define ulong ulongxx /* interferes with system includes */
#include <math.h>
#undef ulong
#include "flint.h"
#include "ulong_extras.h"
int n_is_perfect_power235(mp_limb_t n)
{
static unsigned char mod63[63] = {7,7,4,0,5,4,0,5,6,5,4,4,0,4,4,0,5,4,5,4,
4,0,5,4,0,5,4,6,7,4,0,4,4,0,4,6,7,5,4,0,4,4,0,5,
4,4,5,4,0,5,4,0,4,4,4,6,4,0,5,4,0,4,6};
static unsigned char mod61[61] = {7,7,0,3,1,1,0,0,2,3,0,6,1,5,5,1,1,0,0,1,
3,4,1,2,2,1,0,3,2,4,0,0,4,2,3,0,1,2,2,1,4,3,1,0,
0,1,1,5,5,1,6,0,3,2,0,0,1,1,3,0,7};
static unsigned char mod44[44] = {7,7,0,2,3,3,0,2,2,3,0,6,7,2,0,2,3,2,0,2,
3,6,0,6,2,3,0,2,2,2,0,2,6,7,0,2,3,3,0,2,2,2,0,6};
static unsigned char mod31[31] = {7,7,3,0,3,5,4,1,3,1,1,0,0,0,1,2,3,0,1,1,
1,0,0,2,0,5,4,2,1,2,6};
unsigned char t;
t = mod31[n%31];
if (!t) return 0;
t &= mod44[n%44];
if (!t) return 0;
t &= mod61[n%61];
if (!t) return 0;
t &= mod63[n%63];
if (t & 1)
{
double x = sqrt((double) n);
mp_limb_t y = (mp_limb_t) (x + 0.5);
if (n == n_pow(y, 2)) return 1;
}
if (t & 2)
{
double x = pow((double) n, 1.0 / 3.0);
mp_limb_t y = (mp_limb_t) (x + 0.5);
if (n == n_pow(y, 3)) return 1;
}
if (t & 4)
{
double x = pow((double) n, 1.0 / 5.0);
mp_limb_t y = (mp_limb_t) (x + 0.5);
if (n == n_pow(y, 5)) return 1;
}
return 0;
}
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