#include "fmpz_vec.h"
#include "fmpz_poly.h"
#include "fmpz_mod.h"
#include "fmpz_mod_vec.h"
#include "fmpz_mod_poly.h"
void _fmpz_mod_poly_mullow(fmpz *res, const fmpz *poly1, slong len1,
const fmpz *poly2, slong len2,
slong n, const fmpz_mod_ctx_t ctx)
{
_fmpz_poly_mullow(res, poly1, len1, poly2, len2, n);
_fmpz_mod_vec_set_fmpz_vec(res, res, n, ctx);
}
void fmpz_mod_poly_mullow(fmpz_mod_poly_t res, const fmpz_mod_poly_t poly1,
const fmpz_mod_poly_t poly2, slong n, const fmpz_mod_ctx_t ctx)
{
const slong len1 = poly1->length;
const slong len2 = poly2->length;
if ((len1 == 0) || (len2 == 0) || (n == 0))
{
fmpz_mod_poly_zero(res, ctx);
return;
}
n = FLINT_MIN(n, len1 + len2 - 1);
if ((res == poly1) || (res == poly2))
{
fmpz *t = _fmpz_vec_init(n);
if (len1 >= len2)
_fmpz_mod_poly_mullow(t, poly1->coeffs, len1, poly2->coeffs, len2, n, ctx);
else
_fmpz_mod_poly_mullow(t, poly2->coeffs, len2, poly1->coeffs, len1, n, ctx);
_fmpz_vec_clear(res->coeffs, res->alloc);
res->coeffs = t;
res->alloc = n;
res->length = n;
_fmpz_mod_poly_normalise(res);
}
else
{
fmpz_mod_poly_fit_length(res, n, ctx);
if (len1 >= len2)
_fmpz_mod_poly_mullow(res->coeffs, poly1->coeffs, len1, poly2->coeffs, len2, n, ctx);
else
_fmpz_mod_poly_mullow(res->coeffs, poly2->coeffs, len2, poly1->coeffs, len1, n, ctx);
_fmpz_mod_poly_set_length(res, n);
_fmpz_mod_poly_normalise(res);
}
}