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:heavy_check_mark: 多項式行列の prefix product
(matrix/polynomial-matrix-prefix-product.hpp)

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#pragma once
#include "fps/formal-power-series.hpp"
#include "fps/sampling-points-shift.hpp"
#include "matrix/matrix.hpp"

// a(k-1) a(k-2) ... a(0)
template <class mint>
Matrix<mint> PolynomialMatrixPrefixProduct(const Matrix<FormalPowerSeries<mint>>& a, long long k) {
  using mat = Matrix<mint>;
  assert(k >= 0 && a.h == a.w);
  int n = a.h, deg = 1;
  for (const auto& f : a.a) deg = max(deg, (int)f.size() - 1);
  while (deg & (deg - 1)) deg++;

  auto shift = [&](const vector<mat>& g, mint x) {
    int d = g.size();
    vector<mat> h(d, mat(n));
    for (int i = 0; i < n; i++) {
      for (int j = 0; j < n; j++) {
        vector<mint> y(d);
        for (int l = 0; l < d; l++) y[l] = g[l].get(i, j);
        auto z = SamplingPointsShift(y, x, d);
        for (int l = 0; l < d; l++) h[l].set(i, j, z[l]);
      }
    }
    return h;
  };

  long long v = 1;
  while ((__int128)deg * v * v < k) v *= 2;
  vector<mat> g(deg + 1, mat(n));
  for (int i = 0; i <= deg; i++) {
    mint x = mint(v) * i;
    for (int j = 0; j < n; j++)
      for (int l = 0; l < n; l++) g[i].set(j, l, a.get(j, l).eval(x));
  }
  mint iv = mint(v).inv();
  for (long long w = 1; w < v; w *= 2) {
    auto g1 = shift(g, mint(w) * iv);
    auto g2 = shift(g, mint(w * deg * v + v) * iv);
    auto g3 = shift(g, mint(w * deg * v + v + w) * iv);
    for (int i = 0; i <= w * deg; i++) {
      g[i] = g1[i] * g[i];
      g2[i] = g3[i] * g2[i];
    }
    g.insert(g.end(), g2.begin(), g2.end() - 1);
  }

  mat ret = mat::id(n);
  long long i = 0;
  while (i + v <= k) {
    ret = g[i / v] * ret;
    i += v;
  }
  while (i < k) {
    mat m(n);
    for (int j = 0; j < n; j++)
      for (int l = 0; l < n; l++) m.set(j, l, a.get(j, l).eval(mint(i)));
    ret = m * ret;
    i++;
  }
  return ret;
}

/**
 * @brief 多項式行列の prefix product
 */
#line 2 "fps/formal-power-series.hpp"

template <class mint>
struct FormalPowerSeries : vector<mint> {
  using vector<mint>::vector;
  using FPS = FormalPowerSeries;
  FormalPowerSeries(const vector<mint>& r) : vector<mint>(r) {}
  FormalPowerSeries(vector<mint>&& r) : vector<mint>(std::move(r)) {}
  FPS& operator=(const vector<mint>& r) {
    vector<mint>::operator=(r);
    return *this;
  }
  FPS& operator+=(const FPS& r) {
    if (r.size() > this->size()) this->resize(r.size());
    for (int i = 0; i < (int)r.size(); i++) (*this)[i] += r[i];
    return *this;
  }
  FPS& operator+=(const mint& r) {
    if (this->empty()) this->resize(1);
    (*this)[0] += r;
    return *this;
  }
  FPS& operator-=(const FPS& r) {
    if (r.size() > this->size()) this->resize(r.size());
    for (int i = 0; i < (int)r.size(); i++) (*this)[i] -= r[i];
    return *this;
  }
  FPS& operator-=(const mint& r) {
    if (this->empty()) this->resize(1);
    (*this)[0] -= r;
    return *this;
  }
  FPS& operator*=(const mint& v) {
    for (int k = 0; k < (int)this->size(); k++) (*this)[k] *= v;
    return *this;
  }
  FPS& operator/=(const FPS& r) {
    if (this->size() < r.size()) {
      this->clear();
      return *this;
    }
    int n = this->size() - r.size() + 1;
    if ((int)r.size() <= 64) {
      FPS f(*this), g(r);
      g.shrink();
      mint coeff = g.at(g.size() - 1).inv();
      for (auto& x : g) x *= coeff;
      int deg = (int)f.size() - (int)g.size() + 1;
      int gs = g.size();
      FPS quo(deg);
      for (int i = deg - 1; i >= 0; i--) {
        quo[i] = f[i + gs - 1];
        for (int j = 0; j < gs; j++) f[i + j] -= quo[i] * g[j];
      }
      *this = quo * coeff;
      this->resize(n, mint(0));
      return *this;
    }
    return *this = ((*this).rev().pre(n) * r.rev().inv(n)).pre(n).rev();
  }
  FPS& operator%=(const FPS& r) {
    *this -= *this / r * r;
    shrink();
    return *this;
  }
  FPS operator+(const FPS& r) const { return FPS(*this) += r; }
  FPS operator+(const mint& v) const { return FPS(*this) += v; }
  FPS operator-(const FPS& r) const { return FPS(*this) -= r; }
  FPS operator-(const mint& v) const { return FPS(*this) -= v; }
  FPS operator*(const FPS& r) const { return FPS(*this) *= r; }
  FPS operator*(const mint& v) const { return FPS(*this) *= v; }
  FPS operator/(const FPS& r) const { return FPS(*this) /= r; }
  FPS operator%(const FPS& r) const { return FPS(*this) %= r; }
  FPS operator-() const {
    FPS ret(this->size());
    for (int i = 0; i < (int)this->size(); i++) ret[i] = -(*this)[i];
    return ret;
  }
  void shrink() {
    while (this->size() && this->back() == mint(0)) this->pop_back();
  }
  FPS rev() const {
    FPS ret(*this);
    reverse(begin(ret), end(ret));
    return ret;
  }
  FPS dot(FPS r) const {
    FPS ret(min(this->size(), r.size()));
    for (int i = 0; i < (int)ret.size(); i++) ret[i] = (*this)[i] * r[i];
    return ret;
  }
  FPS pre(int sz) const {
    return FPS(begin(*this), begin(*this) + min((int)this->size(), sz));
  }
  FPS operator>>=(int sz) {
    assert(sz >= 0);
    if ((int)this->size() <= sz)
      this->clear();
    else
      this->erase(this->begin(), this->begin() + sz);
    return *this;
  }
  FPS operator>>(int sz) const {
    if ((int)this->size() <= sz) return {};
    FPS ret(*this);
    ret.erase(ret.begin(), ret.begin() + sz);
    return ret;
  }
  FPS operator<<=(int sz) {
    assert(sz >= 0);
    this->insert(this->begin(), sz, mint(0));
    return *this;
  }
  FPS operator<<(int sz) const {
    FPS ret(*this);
    ret.insert(ret.begin(), sz, mint(0));
    return ret;
  }
  FPS diff() const {
    const int n = (int)this->size();
    FPS ret(max(0, n - 1));
    mint one(1), coeff(1);
    for (int i = 1; i < n; i++) {
      ret[i - 1] = (*this)[i] * coeff;
      coeff += one;
    }
    return ret;
  }
  FPS integral() const {
    const int n = (int)this->size();
    FPS ret(n + 1);
    ret[0] = mint(0);
    if (n > 0) ret[1] = mint(1);
    auto mod = mint::get_mod();
    for (int i = 2; i <= n; i++) ret[i] = (-ret[mod % i]) * (mod / i);
    for (int i = 0; i < n; i++) ret[i + 1] *= (*this)[i];
    return ret;
  }
  mint eval(mint x) const {
    mint r = 0, w = 1;
    for (auto& v : *this) r += w * v, w *= x;
    return r;
  }
  FPS log(int deg = -1) const {
    assert((*this)[0] == mint(1));
    if (deg == -1) deg = (int)this->size();
    return (this->diff() * this->inv(deg)).pre(deg - 1).integral();
  }
  FPS pow(int64_t k, int deg = -1) const {
    const int n = (int)this->size();
    if (deg == -1) deg = n;
    if (k == 0) {
      FPS ret(deg);
      if (deg) ret[0] = 1;
      return ret;
    }
    for (int i = 0; i < n; i++) {
      if ((*this)[i] != mint(0)) {
        mint rev = mint(1) / (*this)[i];
        FPS ret = (((*this * rev) >> i).log(deg) * k).exp(deg);
        ret *= (*this)[i].pow(k);
        ret = (ret << (i * k)).pre(deg);
        if ((int)ret.size() < deg) ret.resize(deg, mint(0));
        return ret;
      }
      if (__int128_t(i + 1) * k >= deg) return FPS(deg, mint(0));
    }
    return FPS(deg, mint(0));
  }

  static void* ntt_ptr;
  static void set_ntt();
  FPS& operator*=(const FPS& r);
  FPS middle_product(const FPS& r) const;
  void ntt();
  void intt();
  void ntt_doubling();
  static int ntt_root();
  FPS inv(int deg = -1) const;
  FPS exp(int deg = -1) const;
};
template <typename mint>
void* FormalPowerSeries<mint>::ntt_ptr = nullptr;
#line 2 "modint/factorial.hpp"

template <class mint>
struct Factorial {
  static void reserve(int n) {
    inv(n);
    fact(n);
    fact_inv(n);
  }
  static mint inv(int n) {
    static long long mod = mint::get_mod();
    static vector<mint> buf({0, 1});
    assert(n != 0);
    if (mod != mint::get_mod()) {
      mod = mint::get_mod();
      buf = vector<mint>({0, 1});
    }
    while ((int)buf.capacity() <= n) buf.reserve(buf.capacity() * 2);
    while ((int)buf.size() <= n) {
      long long k = buf.size(), q = (mod + k - 1) / k;
      buf.push_back(q * buf[k * q - mod]);
    }
    return buf[n];
  }
  static mint fact(int n) {
    static long long mod = mint::get_mod();
    static vector<mint> buf({1, 1});
    assert(n >= 0);
    if (mod != mint::get_mod()) {
      mod = mint::get_mod();
      buf = vector<mint>({1, 1});
    }
    while ((int)buf.capacity() <= n) buf.reserve(buf.capacity() * 2);
    while ((int)buf.size() <= n) {
      long long k = buf.size();
      buf.push_back(buf.back() * k);
    }
    return buf[n];
  }
  static mint fact_inv(int n) {
    static long long mod = mint::get_mod();
    static vector<mint> buf({1, 1});
    assert(n >= 0);
    if (mod != mint::get_mod()) {
      mod = mint::get_mod();
      buf = vector<mint>({1, 1});
    }
    if ((int)buf.size() <= n) inv(n);
    while ((int)buf.capacity() <= n) buf.reserve(buf.capacity() * 2);
    while ((int)buf.size() <= n) {
      long long k = buf.size();
      buf.push_back(buf.back() * inv(k));
    }
    return buf[n];
  }
  static mint binom(int n, int r) {
    if (r < 0 || r > n) return 0;
    return fact(n) * fact_inv(r) * fact_inv(n - r);
  }
  static mint binom_naive(int n, int r) {
    if (r < 0 || r > n) return 0;
    mint res = fact_inv(r);
    for (int i = 0; i < r; i++) res *= n - i;
    return res;
  }
  static mint multinom(const vector<int>& r) {
    int n = 0;
    for (auto& x : r) {
      if (x < 0) return 0;
      n += x;
    }
    mint res = fact(n);
    for (auto& x : r) res *= fact_inv(x);
    return res;
  }
  static mint P(int n, int r) {
    if (r < 0 || r > n) return 0;
    return fact(n) * fact_inv(n - r);
  }
  // partition n items to r groups (allow empty group)
  static mint H(int n, int r) {
    if (n < 0 || r < 0) return 0;
    return r == 0 ? 1 : binom(n + r - 1, r);
  }
};
/**
 * @brief 階乗, 二項係数
 */
#line 4 "fps/sampling-points-shift.hpp"

// f(0),f(1),...,f(n-1) -> f(c),...,f(c+m-1)
template <class mint>
vector<mint> SamplingPointsShift(const vector<mint>& f, mint c, int m) {
  using fps = FormalPowerSeries<mint>;
  using fact = Factorial<mint>;
  int n = f.size();
  fact::reserve(m);
  fps f1(n), ei(n);
  for (int i = 0; i < n; i++) f1[i] = f[i] * fact::fact_inv(i);
  for (int i = 0; i < n; i++) ei[i] = fact::fact_inv(i) * (i % 2 ? -1 : 1);
  f1 *= ei;
  for (int i = n; i < f1.size(); i++) f1[i] = 0;
  for (int i = 0; i < n; i++) f1[i] *= fact::fact(i);
  fps g(n, 1);
  for (int i = 1; i < n; i++) g[i] = g[i - 1] * (c + 1 - i) * fact::inv(i);
  g = g.middle_product(f1);
  for (int i = 0; i < n; i++) g[i] *= fact::fact_inv(i);
  fps e(m);
  for (int i = 0; i < m; i++) e[i] = fact::fact_inv(i);
  g *= e;
  g.resize(m);
  for (int i = 0; i < m; i++) g[i] *= fact::fact(i);
  return g;
}
/**
 * @brief 評価点シフト
 * @docs docs/fps/sampling-points-shift.md
 */
#line 2 "matrix/matrix.hpp"

template <class T>
struct Matrix {
  int h, w;
  vector<T> a;
  Matrix() {}
  Matrix(int n) : h(n), w(n), a(n * n, T{}) {}
  Matrix(int h_, int w_) : h(h_), w(w_), a(h * w, T{}) {}
  inline T get(int i, int j) const { return a[w * i + j]; }
  inline void set(int i, int j, T v) { a[w * i + j] = v; }
  inline void add(int i, int j, T v) { a[w * i + j] += v; }
  inline void sub(int i, int j, T v) { a[w * i + j] -= v; }
  static Matrix id(int n) {
    Matrix mat(n);
    for (int i = 0; i < n; i++) mat.a[n * i + i] = T(1);
    return mat;
  }
  Matrix operator+=(const Matrix& r) {
    assert(h == r.h && w == r.w);
    for (int i = 0; i < h * w; i++) a[i] += r.a[i];
    return *this;
  }
  Matrix operator-=(const Matrix& r) {
    assert(h == r.h && w == r.w);
    for (int i = 0; i < h * w; i++) a[i] -= r.a[i];
    return *this;
  }
  Matrix operator+(const Matrix& r) { return Matrix(*this) += r; }
  Matrix operator-(const Matrix& r) { return Matrix(*this) -= r; }
  Matrix operator*(const Matrix& r) {
    assert(w == r.h);
    Matrix ret(h, r.w);
    for (int i = 0; i < h; i++)
      for (int j = 0; j < r.w; j++)
        for (int k = 0; k < w; k++)
          ret.add(i, j, get(i, k) * r.get(k, j));
    return ret;
  }
  Matrix& operator*=(const Matrix& r) { return *this = *this * r; }
  Matrix& operator*=(T r) {
    for (auto& v : a) v *= r;
    return *this;
  }
  Matrix operator*(T r) { return Matrix(*this) *= r; }
  Matrix pow(long long n) const {
    Matrix ret = id(h);
    Matrix mat(*this);
    while (n > 0) {
      if (n & 1) ret = ret * mat;
      mat = mat * mat;
      n >>= 1;
    }
    return ret;
  }

  T det() const {
    assert(h == w);
    Matrix mat(*this);
    T zero{}, det(1);
    for (int k = 0; k < h; k++) {
      {
        int i = k;
        while (i < h && mat.get(i, k) == zero) i++;
        if (i == h) return zero;
        if (i != k) {
          mat.swap_row(i, k);
          det = -det;
        }
      }
      for (int i = k + 1; i < h; i++)
        mat.mul_add_row(i, k, -mat.get(i, k) / mat.get(k, k));
      det *= mat.a[h * k + k];
    }
    return det;
  }
  optional<Matrix> inv() const {
    assert(h == w);
    Matrix mat(*this);
    Matrix imat = id(h);
    T zero{};
    for (int k = 0; k < h; k++) {
      {
        int i = k;
        while (i < h && mat.get(i, k) == zero) i++;
        if (i == h) return nullopt;
        if (i != k) {
          mat.swap_row(i, k);
          imat.swap_row(i, k);
        }
      }
      {
        T v = T(1) / mat.get(k, k);
        mat.mul_row(k, v);
        imat.mul_row(k, v);
      }
      for (int i = 0; i < h; i++) {
        if (i == k) continue;
        T v = -mat.get(i, k);
        mat.mul_add_row(i, k, v);
        imat.mul_add_row(i, k, v);
      }
    }
    return imat;
  }
  void swap_row(int i, int j) {
    for (int k = 0; k < w; k++) swap(a[w * i + k], a[w * j + k]);
  }
  void mul_row(int i, T v) {
    for (int k = 0; k < w; k++) a[w * i + k] *= v;
  }
  // row i += row j * v
  void mul_add_row(int i, int j, T v) {
    for (int k = 0; k < w; k++) a[w * i + k] += a[w * j + k] * v;
  }
  friend ostream& operator<<(ostream& os, const Matrix& mat) {
    for (int i = 0; i < mat.h; i++) {
      for (int j = 0; j < mat.w; j++) {
        os << mat.get(i, j);
        if (j + 1 < mat.w) os << " ";
      }
      if (i + 1 < mat.h) os << "\n";
    }
    return os;
  }
};
#line 5 "matrix/polynomial-matrix-prefix-product.hpp"

// a(k-1) a(k-2) ... a(0)
template <class mint>
Matrix<mint> PolynomialMatrixPrefixProduct(const Matrix<FormalPowerSeries<mint>>& a, long long k) {
  using mat = Matrix<mint>;
  assert(k >= 0 && a.h == a.w);
  int n = a.h, deg = 1;
  for (const auto& f : a.a) deg = max(deg, (int)f.size() - 1);
  while (deg & (deg - 1)) deg++;

  auto shift = [&](const vector<mat>& g, mint x) {
    int d = g.size();
    vector<mat> h(d, mat(n));
    for (int i = 0; i < n; i++) {
      for (int j = 0; j < n; j++) {
        vector<mint> y(d);
        for (int l = 0; l < d; l++) y[l] = g[l].get(i, j);
        auto z = SamplingPointsShift(y, x, d);
        for (int l = 0; l < d; l++) h[l].set(i, j, z[l]);
      }
    }
    return h;
  };

  long long v = 1;
  while ((__int128)deg * v * v < k) v *= 2;
  vector<mat> g(deg + 1, mat(n));
  for (int i = 0; i <= deg; i++) {
    mint x = mint(v) * i;
    for (int j = 0; j < n; j++)
      for (int l = 0; l < n; l++) g[i].set(j, l, a.get(j, l).eval(x));
  }
  mint iv = mint(v).inv();
  for (long long w = 1; w < v; w *= 2) {
    auto g1 = shift(g, mint(w) * iv);
    auto g2 = shift(g, mint(w * deg * v + v) * iv);
    auto g3 = shift(g, mint(w * deg * v + v + w) * iv);
    for (int i = 0; i <= w * deg; i++) {
      g[i] = g1[i] * g[i];
      g2[i] = g3[i] * g2[i];
    }
    g.insert(g.end(), g2.begin(), g2.end() - 1);
  }

  mat ret = mat::id(n);
  long long i = 0;
  while (i + v <= k) {
    ret = g[i / v] * ret;
    i += v;
  }
  while (i < k) {
    mat m(n);
    for (int j = 0; j < n; j++)
      for (int l = 0; l < n; l++) m.set(j, l, a.get(j, l).eval(mint(i)));
    ret = m * ret;
    i++;
  }
  return ret;
}

/**
 * @brief 多項式行列の prefix product
 */
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