namespace GiNaC {
-bool normalize_in_field(umodpoly& a, cln::cl_MI* content_ = 0);
+bool normalize_in_field(umodpoly& a, cln::cl_MI* content_ = nullptr);
/// Make the univariate polynomial @a x unit normal. This version is used
/// for rings which are not fields.
/// Returns true if the polynomial @x is already unit normal, and false
/// otherwise.
template<typename T> bool
-normalize_in_ring(T& x, typename T::value_type* content_ = 0, int* unit_ = 0)
+normalize_in_ring(T& x, typename T::value_type* content_ = nullptr, int* unit_ = nullptr)
{
typedef typename T::value_type ring_t;
static const ring_t one(1);