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| template <int Mod>
class ModInt {
public:
int n;
constexpr ModInt(const int x = 0) noexcept : n((x % Mod + Mod) % Mod) {}
constexpr int &value() noexcept { return n; }
constexpr const int &value() const noexcept { return n; }
constexpr ModInt operator+(const ModInt rhs) const noexcept { return ModInt(*this) += rhs; }
constexpr ModInt operator-(const ModInt rhs) const noexcept { return ModInt(*this) -= rhs; }
constexpr ModInt operator*(const ModInt rhs) const noexcept { return ModInt(*this) *= rhs; }
constexpr ModInt operator/(const ModInt rhs) const noexcept { return ModInt(*this) /= rhs; }
constexpr ModInt &operator+=(const ModInt rhs) noexcept {
n += rhs.n;
if (n >= Mod)
n -= Mod;
return *this;
}
constexpr ModInt &operator-=(const ModInt rhs) noexcept {
if (n < rhs.n)
n += Mod;
n -= rhs.n;
return *this;
}
constexpr ModInt &operator*=(const ModInt rhs) noexcept {
n = n * rhs.n % Mod;
return *this;
}
constexpr ModInt &operator/=(ModInt rhs) noexcept {
int exp = Mod - 2;
while (exp) {
if (exp % 2)
*this *= rhs;
rhs *= rhs;
exp /= 2;
}
return *this;
}
friend std::istream &operator>>(std::istream &_istr, ModInt &rhs) {
_istr >> rhs.n;
rhs.n = (rhs.n % Mod + Mod) % Mod;
return _istr;
}
friend std::ostream &operator<<(std::ostream &_ostr, const ModInt &rhs) {
return _ostr << rhs.n;
}
};
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