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/*
Copyright (C) 2010,2011 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 "perm.h"
#include "fmpz.h"
#include "fmpz_mat.h"
int
fmpz_mat_randpermdiag(fmpz_mat_t mat, flint_rand_t state,
const fmpz * diag, slong n)
{
int parity;
slong i;
slong * rows;
slong * cols;
rows = _perm_init(mat->r);
cols = _perm_init(mat->c);
parity = _perm_randtest(rows, mat->r, state);
parity ^= _perm_randtest(cols, mat->c, state);
fmpz_mat_zero(mat);
for (i = 0; i < n; i++)
fmpz_set(fmpz_mat_entry(mat, rows[i], cols[i]), diag + i);
_perm_clear(rows);
_perm_clear(cols);
return parity;
}