tourist's modular arithmetic class

#include 
 
using namespace std;
 
template 
T inverse(T a, T m) {
  T u = 0, v = 1;
  while (a != 0) {
    T t = m / a;
    m -= t * a; swap(a, m);
    u -= t * v; swap(u, v);
  }
  assert(m == 1);
  return u;
}
 
template 
class Modular {
 public:
  using Type = typename decay::type;
 
  constexpr Modular() : value() {}
  template 
  Modular(const U& x) {
    value = normalize(x);
  }
 
  template 
  static Type normalize(const U& x) {
    Type v;
    if (-mod() <= x && x < mod()) v = static_cast(x);
    else v = static_cast(x % mod());
    if (v < 0) v += mod();
    return v;
  }
 
  const Type& operator()() const { return value; }
  template 
  explicit operator U() const { return static_cast(value); }
  constexpr static Type mod() { return T::value; }
 
  Modular& operator+=(const Modular& other) { if ((value += other.value) >= mod()) value -= mod(); return *this; }
  Modular& operator-=(const Modular& other) { if ((value -= other.value) < 0) value += mod(); return *this; }
  template  Modular& operator+=(const U& other) { return *this += Modular(other); }
  template  Modular& operator-=(const U& other) { return *this -= Modular(other); }
  Modular& operator++() { return *this += 1; }
  Modular& operator--() { return *this -= 1; }
  Modular operator++(int) { Modular result(*this); *this += 1; return result; }
  Modular operator--(int) { Modular result(*this); *this -= 1; return result; }
  Modular operator-() const { return Modular(-value); }
 
  template 
  typename enable_if::Type, int>::value, Modular>::type& operator*=(const Modular& rhs) {
#ifdef _WIN32
    uint64_t x = static_cast(value) * static_cast(rhs.value);
    uint32_t xh = static_cast(x >> 32), xl = static_cast(x), d, m;
    asm(
      "divl %4; \n\t"
      : "=a" (d), "=d" (m)
      : "d" (xh), "a" (xl), "r" (mod())
    );
    value = m;
#else
    value = normalize(static_cast(value) * static_cast(rhs.value));
#endif
    return *this;
  }
  template 
  typename enable_if::Type, int64_t>::value, Modular>::type& operator*=(const Modular& rhs) {
    int64_t q = static_cast(static_cast(value) * rhs.value / mod());
    value = normalize(value * rhs.value - q * mod());
    return *this;
  }
  template 
  typename enable_if::Type>::value, Modular>::type& operator*=(const Modular& rhs) {
    value = normalize(value * rhs.value);
    return *this;
  }
 
  Modular& operator/=(const Modular& other) { return *this *= Modular(inverse(other.value, mod())); }
 
  template 
  friend const Modular& abs(const Modular& v) { return v; }
 
  template 
  friend bool operator==(const Modular& lhs, const Modular& rhs);
 
  template 
  friend bool operator<(const Modular& lhs, const Modular& rhs);
 
  template 
  friend std::istream& operator>>(std::istream& stream, Modular& number);
 
 private:
  Type value;
};
 
template  bool operator==(const Modular& lhs, const Modular& rhs) { return lhs.value == rhs.value; }
template  bool operator==(const Modular& lhs, U rhs) { return lhs == Modular(rhs); }
template  bool operator==(U lhs, const Modular& rhs) { return Modular(lhs) == rhs; }
 
template  bool operator!=(const Modular& lhs, const Modular& rhs) { return !(lhs == rhs); }
template  bool operator!=(const Modular& lhs, U rhs) { return !(lhs == rhs); }
template  bool operator!=(U lhs, const Modular& rhs) { return !(lhs == rhs); }
 
template  bool operator<(const Modular& lhs, const Modular& rhs) { return lhs.value < rhs.value; }
 
template  Modular operator+(const Modular& lhs, const Modular& rhs) { return Modular(lhs) += rhs; }
template  Modular operator+(const Modular& lhs, U rhs) { return Modular(lhs) += rhs; }
template  Modular operator+(U lhs, const Modular& rhs) { return Modular(lhs) += rhs; }
 
template  Modular operator-(const Modular& lhs, const Modular& rhs) { return Modular(lhs) -= rhs; }
template  Modular operator-(const Modular& lhs, U rhs) { return Modular(lhs) -= rhs; }
template  Modular operator-(U lhs, const Modular& rhs) { return Modular(lhs) -= rhs; }
 
template  Modular operator*(const Modular& lhs, const Modular& rhs) { return Modular(lhs) *= rhs; }
template  Modular operator*(const Modular& lhs, U rhs) { return Modular(lhs) *= rhs; }
template  Modular operator*(U lhs, const Modular& rhs) { return Modular(lhs) *= rhs; }
 
template  Modular operator/(const Modular& lhs, const Modular& rhs) { return Modular(lhs) /= rhs; }
template  Modular operator/(const Modular& lhs, U rhs) { return Modular(lhs) /= rhs; }
template  Modular operator/(U lhs, const Modular& rhs) { return Modular(lhs) /= rhs; }
 
template
Modular power(const Modular& a, const U& b) {
  assert(b >= 0);
  Modular x = a, res = 1;
  U p = b;
  while (p > 0) {
    if (p & 1) res *= x;
    x *= x;
    p >>= 1;
  }
  return res;
}
 
template 
bool IsZero(const Modular& number) {
  return number() == 0;
}
 
template 
string to_string(const Modular& number) {
  return to_string(number());
}
 
template 
std::ostream& operator<<(std::ostream& stream, const Modular& number) {
  return stream << number();
}
 
template 
std::istream& operator>>(std::istream& stream, Modular& number) {
  typename common_type::Type, int64_t>::type x;
  stream >> x;
  number.value = Modular::normalize(x);
  return stream;
}
 
/*
using ModType = int;
 
struct VarMod { static ModType value; };
ModType VarMod::value;
ModType& md = VarMod::value;
using Mint = Modular;
*/
 
constexpr int md = 998244353;
using Mint = Modular::type, md>>;

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