poly/lagrange_interpolate_iota.hpp

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• Last update: 2023-12-29 16:32:29+09:00
• Include: #include "poly/lagrange_interpolate_iota.hpp"

Depends on

• alg/monoid/mul.hpp
• ds/sliding_window_aggregation.hpp
• mod/crt3.hpp
• mod/mod_inv.hpp
• mod/modint.hpp
• mod/modint_common.hpp
• poly/convolution.hpp
• poly/convolution_karatsuba.hpp
• poly/convolution_naive.hpp
• poly/fft.hpp
• poly/ntt.hpp

Required by

• poly/from_log_differentiation.hpp
• poly/prefix_product_of_poly.hpp
• poly/sparse_exp_of_div.hpp
• seq/interpolate_poly_exp_sum.hpp
• seq/kth_term_of_p_recursive.hpp

Verified with

• test/library_checker/math/factorial.test.cpp
• test/library_checker/math/sum_of_exp_times_poly.test.cpp
• test/library_checker/polynomial/shift_of_sampling_points_of_polynomial.test.cpp
• test/mytest/factorial_998.test.cpp
• test/yukicoder/1080_2.test.cpp
• test/yukicoder/2166.test.cpp
• test/yukicoder/502_2.test.cpp
• test_atcoder/abc222h_2.test.cpp
• test_atcoder/abc276_g.test.cpp
• test_atcoder/abc276_g_2.test.cpp

Code

#pragma once
#include "alg/monoid/mul.hpp"

#include "ds/sliding_window_aggregation.hpp"

#include "poly/convolution.hpp"


// Input: f(0), ..., f(n-1) and c. Return: f(c)

template <typename T, typename enable_if<has_mod<T>::value>::type * = nullptr>
T lagrange_interpolate_iota(vc<T> &f, T c) {
  int n = len(f);
  if (int(c.val) < n) return f[c.val];
  auto a = f;
  FOR(i, n) {
    a[i] = a[i] * fact_inv<T>(i) * fact_inv<T>(n - 1 - i);
    if ((n - 1 - i) & 1) a[i] = -a[i];
  }
  vc<T> lp(n + 1), rp(n + 1);
  lp[0] = rp[n] = 1;
  FOR(i, n) lp[i + 1] = lp[i] * (c - i);
  FOR_R(i, n) rp[i] = rp[i + 1] * (c - i);
  T ANS = 0;
  FOR(i, n) ANS += a[i] * lp[i] * rp[i + 1];
  return ANS;
}

// mod じゃない場合。かなり低次の多項式を想定している。O(n^2)

// Input: f(0), ..., f(n-1) and c. Return: f(c)

template <typename T, typename enable_if<!has_mod<T>::value>::type * = nullptr>
T lagrange_interpolate_iota(vc<T> &f, T c) {
  const int LIM = 10;
  int n = len(f);
  assert(n < LIM);

  // (-1)^{i-j} binom(i,j)

  static vvc<int> C;
  if (C.empty()) {
    C.assign(LIM, vc<int>(LIM));
    C[0][0] = 1;
    FOR(n, 1, LIM) FOR(k, n + 1) {
      C[n][k] += C[n - 1][k];
      if (k) C[n][k] += C[n - 1][k - 1];
    }
    FOR(n, LIM) FOR(k, n + 1) if ((n + k) % 2) C[n][k] = -C[n][k];
  }
  // f(x) = sum a_i binom(x,i)

  vc<T> a(n);
  FOR(i, n) FOR(j, i + 1) { a[i] += f[j] * C[i][j]; }

  T res = 0;
  T b = 1;
  FOR(i, n) {
    res += a[i] * b;
    b = b * (c - i) / (1 + i);
  }
  return res;
}

// Input: f(0), ..., f(n-1) and c, m

// Return: f(c), f(c+1), ..., f(c+m-1)

// Complexity: M(n, n + m)

template <typename mint>
vc<mint> lagrange_interpolate_iota(vc<mint> &f, mint c, int m) {
  if (m <= 60) {
    vc<mint> ANS(m);
    FOR(i, m) ANS[i] = lagrange_interpolate_iota(f, c + mint(i));
    return ANS;
  }
  ll n = len(f);
  auto a = f;
  FOR(i, n) {
    a[i] = a[i] * fact_inv<mint>(i) * fact_inv<mint>(n - 1 - i);
    if ((n - 1 - i) & 1) a[i] = -a[i];
  }
  // x = c, c+1, ... に対して a0/x + a1/(x-1) + ... を求めておく

  vc<mint> b(n + m - 1);
  FOR(i, n + m - 1) b[i] = mint(1) / (c + mint(i - n + 1));
  a = convolution(a, b);

  Sliding_Window_Aggregation<Monoid_Mul<mint>> swag;
  vc<mint> ANS(m);
  ll L = 0, R = 0;
  FOR(i, m) {
    while (L < i) { swag.pop(), ++L; }
    while (R - L < n) { swag.push(c + mint((R++) - n + 1)); }
    auto coef = swag.prod();
    if (coef == 0) {
      ANS[i] = f[(c + i).val];
    } else {
      ANS[i] = a[i + n - 1] * coef;
    }
  }
  return ANS;
}

#line 2 "alg/monoid/mul.hpp"

template <class T>
struct Monoid_Mul {
  using value_type = T;
  using X = T;
  static constexpr X op(const X &x, const X &y) noexcept { return x * y; }
  static constexpr X inverse(const X &x) noexcept { return X(1) / x; }
  static constexpr X unit() { return X(1); }
  static constexpr bool commute = true;
};
#line 1 "ds/sliding_window_aggregation.hpp"
template <class Monoid>
struct Sliding_Window_Aggregation {
  using X = typename Monoid::value_type;
  using value_type = X;
  int sz = 0;
  vc<X> dat;
  vc<X> cum_l;
  X cum_r;

  Sliding_Window_Aggregation()
      : cum_l({Monoid::unit()}), cum_r(Monoid::unit()) {}

  int size() { return sz; }

  void push(X x) {
    ++sz;
    cum_r = Monoid::op(cum_r, x);
    dat.eb(x);
  }

  void pop() {
    --sz;
    cum_l.pop_back();
    if (len(cum_l) == 0) {
      cum_l = {Monoid::unit()};
      cum_r = Monoid::unit();
      while (len(dat) > 1) {
        cum_l.eb(Monoid::op(dat.back(), cum_l.back()));
        dat.pop_back();
      }
      dat.pop_back();
    }
  }

  X lprod() { return cum_l.back(); }
  X rprod() { return cum_r; }

  X prod() { return Monoid::op(cum_l.back(), cum_r); }
};

// 定数倍は目に見えて遅くなるので、queue でよいときは使わない
template <class Monoid>
struct SWAG_deque {
  using X = typename Monoid::value_type;
  using value_type = X;
  int sz;
  vc<X> dat_l, dat_r;
  vc<X> cum_l, cum_r;

  SWAG_deque() : sz(0), cum_l({Monoid::unit()}), cum_r({Monoid::unit()}) {}

  int size() { return sz; }

  void push_back(X x) {
    ++sz;
    dat_r.eb(x);
    cum_r.eb(Monoid::op(cum_r.back(), x));
  }

  void push_front(X x) {
    ++sz;
    dat_l.eb(x);
    cum_l.eb(Monoid::op(x, cum_l.back()));
  }

  void push(X x) { push_back(x); }

  void clear() {
    sz = 0;
    dat_l.clear(), dat_r.clear();
    cum_l = {Monoid::unit()}, cum_r = {Monoid::unit()};
  }

  void pop_front() {
    if (sz == 1) return clear();
    if (dat_l.empty()) rebuild();
    --sz;
    dat_l.pop_back();
    cum_l.pop_back();
  }

  void pop_back() {
    if (sz == 1) return clear();
    if (dat_r.empty()) rebuild();
    --sz;
    dat_r.pop_back();
    cum_r.pop_back();
  }

  void pop() { pop_front(); }

  X lprod() { return cum_l.back(); }
  X rprod() { return cum_r.back(); }
  X prod() { return Monoid::op(cum_l.back(), cum_r.back()); }
  X prod_all() { return prod(); }

private:
  void rebuild() {
    vc<X> X;
    FOR_R(i, len(dat_l)) X.eb(dat_l[i]);
    X.insert(X.end(), all(dat_r));
    clear();
    int m = len(X) / 2;
    FOR_R(i, m) push_front(X[i]);
    FOR(i, m, len(X)) push_back(X[i]);
    assert(sz == len(X));
  }
};
#line 2 "mod/modint_common.hpp"

struct has_mod_impl {
  template <class T>
  static auto check(T &&x) -> decltype(x.get_mod(), std::true_type{});
  template <class T>
  static auto check(...) -> std::false_type;
};

template <class T>
class has_mod : public decltype(has_mod_impl::check<T>(std::declval<T>())) {};

template <typename mint>
mint inv(int n) {
  static const int mod = mint::get_mod();
  static vector<mint> dat = {0, 1};
  assert(0 <= n);
  if (n >= mod) n %= mod;
  while (len(dat) <= n) {
    int k = len(dat);
    int q = (mod + k - 1) / k;
    dat.eb(dat[k * q - mod] * mint::raw(q));
  }
  return dat[n];
}

template <typename mint>
mint fact(int n) {
  static const int mod = mint::get_mod();
  assert(0 <= n && n < mod);
  static vector<mint> dat = {1, 1};
  while (len(dat) <= n) dat.eb(dat[len(dat) - 1] * mint::raw(len(dat)));
  return dat[n];
}

template <typename mint>
mint fact_inv(int n) {
  static vector<mint> dat = {1, 1};
  if (n < 0) return mint(0);
  while (len(dat) <= n) dat.eb(dat[len(dat) - 1] * inv<mint>(len(dat)));
  return dat[n];
}

template <class mint, class... Ts>
mint fact_invs(Ts... xs) {
  return (mint(1) * ... * fact_inv<mint>(xs));
}

template <typename mint, class Head, class... Tail>
mint multinomial(Head &&head, Tail &&... tail) {
  return fact<mint>(head) * fact_invs<mint>(std::forward<Tail>(tail)...);
}

template <typename mint>
mint C_dense(int n, int k) {
  static vvc<mint> C;
  static int H = 0, W = 0;
  auto calc = [&](int i, int j) -> mint {
    if (i == 0) return (j == 0 ? mint(1) : mint(0));
    return C[i - 1][j] + (j ? C[i - 1][j - 1] : 0);
  };
  if (W <= k) {
    FOR(i, H) {
      C[i].resize(k + 1);
      FOR(j, W, k + 1) { C[i][j] = calc(i, j); }
    }
    W = k + 1;
  }
  if (H <= n) {
    C.resize(n + 1);
    FOR(i, H, n + 1) {
      C[i].resize(W);
      FOR(j, W) { C[i][j] = calc(i, j); }
    }
    H = n + 1;
  }
  return C[n][k];
}

template <typename mint, bool large = false, bool dense = false>
mint C(ll n, ll k) {
  assert(n >= 0);
  if (k < 0 || n < k) return 0;
  if constexpr (dense) return C_dense<mint>(n, k);
  if constexpr (!large) return multinomial<mint>(n, k, n - k);
  k = min(k, n - k);
  mint x(1);
  FOR(i, k) x *= mint(n - i);
  return x * fact_inv<mint>(k);
}

template <typename mint, bool large = false>
mint C_inv(ll n, ll k) {
  assert(n >= 0);
  assert(0 <= k && k <= n);
  if (!large) return fact_inv<mint>(n) * fact<mint>(k) * fact<mint>(n - k);
  return mint(1) / C<mint, 1>(n, k);
}

// [x^d](1-x)^{-n}
template <typename mint, bool large = false, bool dense = false>
mint C_negative(ll n, ll d) {
  assert(n >= 0);
  if (d < 0) return mint(0);
  if (n == 0) { return (d == 0 ? mint(1) : mint(0)); }
  return C<mint, large, dense>(n + d - 1, d);
}
#line 3 "mod/modint.hpp"

template <int mod>
struct modint {
  static constexpr u32 umod = u32(mod);
  static_assert(umod < u32(1) << 31);
  u32 val;

  static modint raw(u32 v) {
    modint x;
    x.val = v;
    return x;
  }
  constexpr modint() : val(0) {}
  constexpr modint(u32 x) : val(x % umod) {}
  constexpr modint(u64 x) : val(x % umod) {}
  constexpr modint(u128 x) : val(x % umod) {}
  constexpr modint(int x) : val((x %= mod) < 0 ? x + mod : x){};
  constexpr modint(ll x) : val((x %= mod) < 0 ? x + mod : x){};
  constexpr modint(i128 x) : val((x %= mod) < 0 ? x + mod : x){};
  bool operator<(const modint &other) const { return val < other.val; }
  modint &operator+=(const modint &p) {
    if ((val += p.val) >= umod) val -= umod;
    return *this;
  }
  modint &operator-=(const modint &p) {
    if ((val += umod - p.val) >= umod) val -= umod;
    return *this;
  }
  modint &operator*=(const modint &p) {
    val = u64(val) * p.val % umod;
    return *this;
  }
  modint &operator/=(const modint &p) {
    *this *= p.inverse();
    return *this;
  }
  modint operator-() const { return modint::raw(val ? mod - val : u32(0)); }
  modint operator+(const modint &p) const { return modint(*this) += p; }
  modint operator-(const modint &p) const { return modint(*this) -= p; }
  modint operator*(const modint &p) const { return modint(*this) *= p; }
  modint operator/(const modint &p) const { return modint(*this) /= p; }
  bool operator==(const modint &p) const { return val == p.val; }
  bool operator!=(const modint &p) const { return val != p.val; }
  modint inverse() const {
    int a = val, b = mod, u = 1, v = 0, t;
    while (b > 0) {
      t = a / b;
      swap(a -= t * b, b), swap(u -= t * v, v);
    }
    return modint(u);
  }
  modint pow(ll n) const {
    assert(n >= 0);
    modint ret(1), mul(val);
    while (n > 0) {
      if (n & 1) ret *= mul;
      mul *= mul;
      n >>= 1;
    }
    return ret;
  }
  static constexpr int get_mod() { return mod; }
  // (n, r), r は 1 の 2^n 乗根
  static constexpr pair<int, int> ntt_info() {
    if (mod == 120586241) return {20, 74066978};
    if (mod == 167772161) return {25, 17};
    if (mod == 469762049) return {26, 30};
    if (mod == 754974721) return {24, 362};
    if (mod == 880803841) return {23, 211};
    if (mod == 943718401) return {22, 663003469};
    if (mod == 998244353) return {23, 31};
    if (mod == 1045430273) return {20, 363};
    if (mod == 1051721729) return {20, 330};
    if (mod == 1053818881) return {20, 2789};
    return {-1, -1};
  }
  static constexpr bool can_ntt() { return ntt_info().fi != -1; }
};

#ifdef FASTIO
template <int mod>
void rd(modint<mod> &x) {
  fastio::rd(x.val);
  x.val %= mod;
  // assert(0 <= x.val && x.val < mod);
}
template <int mod>
void wt(modint<mod> x) {
  fastio::wt(x.val);
}
#endif

using modint107 = modint<1000000007>;
using modint998 = modint<998244353>;
#line 2 "mod/mod_inv.hpp"

// long でも大丈夫

// (val * x - 1) が mod の倍数になるようにする

// 特に mod=0 なら x=0 が満たす

ll mod_inv(ll val, ll mod) {
  if (mod == 0) return 0;
  mod = abs(mod);
  val %= mod;
  if (val < 0) val += mod;
  ll a = val, b = mod, u = 1, v = 0, t;
  while (b > 0) {
    t = a / b;
    swap(a -= t * b, b), swap(u -= t * v, v);
  }
  if (u < 0) u += mod;
  return u;
}
#line 1 "mod/crt3.hpp"

constexpr u32 mod_pow_constexpr(u64 a, u64 n, u32 mod) {
  a %= mod;
  u64 res = 1;
  FOR(32) {
    if (n & 1) res = res * a % mod;
    a = a * a % mod, n /= 2;
  }
  return res;
}

template <typename T, u32 p0, u32 p1, u32 p2>
T CRT3(u64 a0, u64 a1, u64 a2) {
  static_assert(p0 < p1 && p1 < p2);
  static constexpr u64 x0_1 = mod_pow_constexpr(p0, p1 - 2, p1);
  static constexpr u64 x01_2 = mod_pow_constexpr(u64(p0) * p1 % p2, p2 - 2, p2);
  u64 c = (a1 - a0 + p1) * x0_1 % p1;
  u64 a = a0 + c * p0;
  c = (a2 - a % p2 + p2) * x01_2 % p2;
  return T(a) + T(c) * T(p0) * T(p1);
}
#line 2 "poly/convolution_naive.hpp"

template <class T, typename enable_if<!has_mod<T>::value>::type* = nullptr>
vc<T> convolution_naive(const vc<T>& a, const vc<T>& b) {
  int n = int(a.size()), m = int(b.size());
  if (n > m) return convolution_naive<T>(b, a);
  if (n == 0) return {};
  vector<T> ans(n + m - 1);
  FOR(i, n) FOR(j, m) ans[i + j] += a[i] * b[j];
  return ans;
}

template <class T, typename enable_if<has_mod<T>::value>::type* = nullptr>
vc<T> convolution_naive(const vc<T>& a, const vc<T>& b) {
  int n = int(a.size()), m = int(b.size());
  if (n > m) return convolution_naive<T>(b, a);
  if (n == 0) return {};
  vc<T> ans(n + m - 1);
  if (n <= 16 && (T::get_mod() < (1 << 30))) {
    for (int k = 0; k < n + m - 1; ++k) {
      int s = max(0, k - m + 1);
      int t = min(n, k + 1);
      u64 sm = 0;
      for (int i = s; i < t; ++i) { sm += u64(a[i].val) * (b[k - i].val); }
      ans[k] = sm;
    }
  } else {
    for (int k = 0; k < n + m - 1; ++k) {
      int s = max(0, k - m + 1);
      int t = min(n, k + 1);
      u128 sm = 0;
      for (int i = s; i < t; ++i) { sm += u64(a[i].val) * (b[k - i].val); }
      ans[k] = T::raw(sm % T::get_mod());
    }
  }
  return ans;
}
#line 2 "poly/convolution_karatsuba.hpp"

// 任意の環でできる
template <typename T>
vc<T> convolution_karatsuba(const vc<T>& f, const vc<T>& g) {
  const int thresh = 30;
  if (min(len(f), len(g)) <= thresh) return convolution_naive(f, g);
  int n = max(len(f), len(g));
  int m = ceil(n, 2);
  vc<T> f1, f2, g1, g2;
  if (len(f) < m) f1 = f;
  if (len(f) >= m) f1 = {f.begin(), f.begin() + m};
  if (len(f) >= m) f2 = {f.begin() + m, f.end()};
  if (len(g) < m) g1 = g;
  if (len(g) >= m) g1 = {g.begin(), g.begin() + m};
  if (len(g) >= m) g2 = {g.begin() + m, g.end()};
  vc<T> a = convolution_karatsuba(f1, g1);
  vc<T> b = convolution_karatsuba(f2, g2);
  FOR(i, len(f2)) f1[i] += f2[i];
  FOR(i, len(g2)) g1[i] += g2[i];
  vc<T> c = convolution_karatsuba(f1, g1);
  vc<T> F(len(f) + len(g) - 1);
  assert(2 * m + len(b) <= len(F));
  FOR(i, len(a)) F[i] += a[i], c[i] -= a[i];
  FOR(i, len(b)) F[2 * m + i] += b[i], c[i] -= b[i];
  if (c.back() == T(0)) c.pop_back();
  FOR(i, len(c)) if (c[i] != T(0)) F[m + i] += c[i];
  return F;
}
#line 2 "poly/ntt.hpp"

template <class mint>
void ntt(vector<mint>& a, bool inverse) {
  assert(mint::can_ntt());
  const int rank2 = mint::ntt_info().fi;
  const int mod = mint::get_mod();
  static array<mint, 30> root, iroot;
  static array<mint, 30> rate2, irate2;
  static array<mint, 30> rate3, irate3;

  assert(rank2 != -1 && len(a) <= (1 << max(0, rank2)));

  static bool prepared = 0;
  if (!prepared) {
    prepared = 1;
    root[rank2] = mint::ntt_info().se;
    iroot[rank2] = mint(1) / root[rank2];
    FOR_R(i, rank2) {
      root[i] = root[i + 1] * root[i + 1];
      iroot[i] = iroot[i + 1] * iroot[i + 1];
    }
    mint prod = 1, iprod = 1;
    for (int i = 0; i <= rank2 - 2; i++) {
      rate2[i] = root[i + 2] * prod;
      irate2[i] = iroot[i + 2] * iprod;
      prod *= iroot[i + 2];
      iprod *= root[i + 2];
    }
    prod = 1, iprod = 1;
    for (int i = 0; i <= rank2 - 3; i++) {
      rate3[i] = root[i + 3] * prod;
      irate3[i] = iroot[i + 3] * iprod;
      prod *= iroot[i + 3];
      iprod *= root[i + 3];
    }
  }

  int n = int(a.size());
  int h = topbit(n);
  assert(n == 1 << h);
  if (!inverse) {
    int len = 0;
    while (len < h) {
      if (h - len == 1) {
        int p = 1 << (h - len - 1);
        mint rot = 1;
        FOR(s, 1 << len) {
          int offset = s << (h - len);
          FOR(i, p) {
            auto l = a[i + offset];
            auto r = a[i + offset + p] * rot;
            a[i + offset] = l + r;
            a[i + offset + p] = l - r;
          }
          rot *= rate2[topbit(~s & -~s)];
        }
        len++;
      } else {
        int p = 1 << (h - len - 2);
        mint rot = 1, imag = root[2];
        for (int s = 0; s < (1 << len); s++) {
          mint rot2 = rot * rot;
          mint rot3 = rot2 * rot;
          int offset = s << (h - len);
          for (int i = 0; i < p; i++) {
            u64 mod2 = u64(mod) * mod;
            u64 a0 = a[i + offset].val;
            u64 a1 = u64(a[i + offset + p].val) * rot.val;
            u64 a2 = u64(a[i + offset + 2 * p].val) * rot2.val;
            u64 a3 = u64(a[i + offset + 3 * p].val) * rot3.val;
            u64 a1na3imag = (a1 + mod2 - a3) % mod * imag.val;
            u64 na2 = mod2 - a2;
            a[i + offset] = a0 + a2 + a1 + a3;
            a[i + offset + 1 * p] = a0 + a2 + (2 * mod2 - (a1 + a3));
            a[i + offset + 2 * p] = a0 + na2 + a1na3imag;
            a[i + offset + 3 * p] = a0 + na2 + (mod2 - a1na3imag);
          }
          rot *= rate3[topbit(~s & -~s)];
        }
        len += 2;
      }
    }
  } else {
    mint coef = mint(1) / mint(len(a));
    FOR(i, len(a)) a[i] *= coef;
    int len = h;
    while (len) {
      if (len == 1) {
        int p = 1 << (h - len);
        mint irot = 1;
        FOR(s, 1 << (len - 1)) {
          int offset = s << (h - len + 1);
          FOR(i, p) {
            u64 l = a[i + offset].val;
            u64 r = a[i + offset + p].val;
            a[i + offset] = l + r;
            a[i + offset + p] = (mod + l - r) * irot.val;
          }
          irot *= irate2[topbit(~s & -~s)];
        }
        len--;
      } else {
        int p = 1 << (h - len);
        mint irot = 1, iimag = iroot[2];
        FOR(s, (1 << (len - 2))) {
          mint irot2 = irot * irot;
          mint irot3 = irot2 * irot;
          int offset = s << (h - len + 2);
          for (int i = 0; i < p; i++) {
            u64 a0 = a[i + offset + 0 * p].val;
            u64 a1 = a[i + offset + 1 * p].val;
            u64 a2 = a[i + offset + 2 * p].val;
            u64 a3 = a[i + offset + 3 * p].val;
            u64 x = (mod + a2 - a3) * iimag.val % mod;
            a[i + offset] = a0 + a1 + a2 + a3;
            a[i + offset + 1 * p] = (a0 + mod - a1 + x) * irot.val;
            a[i + offset + 2 * p] = (a0 + a1 + 2 * mod - a2 - a3) * irot2.val;
            a[i + offset + 3 * p] = (a0 + 2 * mod - a1 - x) * irot3.val;
          }
          irot *= irate3[topbit(~s & -~s)];
        }
        len -= 2;
      }
    }
  }
}
#line 1 "poly/fft.hpp"
namespace CFFT {
using real = double;

struct C {
  real x, y;

  C() : x(0), y(0) {}

  C(real x, real y) : x(x), y(y) {}
  inline C operator+(const C& c) const { return C(x + c.x, y + c.y); }
  inline C operator-(const C& c) const { return C(x - c.x, y - c.y); }
  inline C operator*(const C& c) const {
    return C(x * c.x - y * c.y, x * c.y + y * c.x);
  }

  inline C conj() const { return C(x, -y); }
};

const real PI = acosl(-1);
int base = 1;
vector<C> rts = {{0, 0}, {1, 0}};
vector<int> rev = {0, 1};

void ensure_base(int nbase) {
  if (nbase <= base) return;
  rev.resize(1 << nbase);
  rts.resize(1 << nbase);
  for (int i = 0; i < (1 << nbase); i++) {
    rev[i] = (rev[i >> 1] >> 1) + ((i & 1) << (nbase - 1));
  }
  while (base < nbase) {
    real angle = PI * 2.0 / (1 << (base + 1));
    for (int i = 1 << (base - 1); i < (1 << base); i++) {
      rts[i << 1] = rts[i];
      real angle_i = angle * (2 * i + 1 - (1 << base));
      rts[(i << 1) + 1] = C(cos(angle_i), sin(angle_i));
    }
    ++base;
  }
}

void fft(vector<C>& a, int n) {
  assert((n & (n - 1)) == 0);
  int zeros = __builtin_ctz(n);
  ensure_base(zeros);
  int shift = base - zeros;
  for (int i = 0; i < n; i++) {
    if (i < (rev[i] >> shift)) { swap(a[i], a[rev[i] >> shift]); }
  }
  for (int k = 1; k < n; k <<= 1) {
    for (int i = 0; i < n; i += 2 * k) {
      for (int j = 0; j < k; j++) {
        C z = a[i + j + k] * rts[j + k];
        a[i + j + k] = a[i + j] - z;
        a[i + j] = a[i + j] + z;
      }
    }
  }
}
} // namespace CFFT
#line 9 "poly/convolution.hpp"

template <class mint>
vector<mint> convolution_ntt(vector<mint> a, vector<mint> b) {
  if (a.empty() || b.empty()) return {};
  int n = int(a.size()), m = int(b.size());
  int sz = 1;
  while (sz < n + m - 1) sz *= 2;

  // sz = 2^k のときの高速化。分割統治的なやつで損しまくるので。

  if ((n + m - 3) <= sz / 2) {
    auto a_last = a.back(), b_last = b.back();
    a.pop_back(), b.pop_back();
    auto c = convolution(a, b);
    c.resize(n + m - 1);
    c[n + m - 2] = a_last * b_last;
    FOR(i, len(a)) c[i + len(b)] += a[i] * b_last;
    FOR(i, len(b)) c[i + len(a)] += b[i] * a_last;
    return c;
  }

  a.resize(sz), b.resize(sz);
  bool same = a == b;
  ntt(a, 0);
  if (same) {
    b = a;
  } else {
    ntt(b, 0);
  }
  FOR(i, sz) a[i] *= b[i];
  ntt(a, 1);
  a.resize(n + m - 1);
  return a;
}

template <typename mint>
vector<mint> convolution_garner(const vector<mint>& a, const vector<mint>& b) {
  int n = len(a), m = len(b);
  if (!n || !m) return {};
  static constexpr int p0 = 167772161;
  static constexpr int p1 = 469762049;
  static constexpr int p2 = 754974721;
  using mint0 = modint<p0>;
  using mint1 = modint<p1>;
  using mint2 = modint<p2>;
  vc<mint0> a0(n), b0(m);
  vc<mint1> a1(n), b1(m);
  vc<mint2> a2(n), b2(m);
  FOR(i, n) a0[i] = a[i].val, a1[i] = a[i].val, a2[i] = a[i].val;
  FOR(i, m) b0[i] = b[i].val, b1[i] = b[i].val, b2[i] = b[i].val;
  auto c0 = convolution_ntt<mint0>(a0, b0);
  auto c1 = convolution_ntt<mint1>(a1, b1);
  auto c2 = convolution_ntt<mint2>(a2, b2);
  vc<mint> c(len(c0));
  FOR(i, n + m - 1) {
    c[i] = CRT3<mint, p0, p1, p2>(c0[i].val, c1[i].val, c2[i].val);
  }
  return c;
}

template <typename R>
vc<double> convolution_fft(const vc<R>& a, const vc<R>& b) {
  using C = CFFT::C;
  int need = (int)a.size() + (int)b.size() - 1;
  int nbase = 1;
  while ((1 << nbase) < need) nbase++;
  CFFT::ensure_base(nbase);
  int sz = 1 << nbase;
  vector<C> fa(sz);
  for (int i = 0; i < sz; i++) {
    double x = (i < (int)a.size() ? a[i] : 0);
    double y = (i < (int)b.size() ? b[i] : 0);
    fa[i] = C(x, y);
  }
  CFFT::fft(fa, sz);
  C r(0, -0.25 / (sz >> 1)), s(0, 1), t(0.5, 0);
  for (int i = 0; i <= (sz >> 1); i++) {
    int j = (sz - i) & (sz - 1);
    C z = (fa[j] * fa[j] - (fa[i] * fa[i]).conj()) * r;
    fa[j] = (fa[i] * fa[i] - (fa[j] * fa[j]).conj()) * r;
    fa[i] = z;
  }
  for (int i = 0; i < (sz >> 1); i++) {
    C A0 = (fa[i] + fa[i + (sz >> 1)]) * t;
    C A1 = (fa[i] - fa[i + (sz >> 1)]) * t * CFFT::rts[(sz >> 1) + i];
    fa[i] = A0 + A1 * s;
  }
  CFFT::fft(fa, sz >> 1);
  vector<double> ret(need);
  for (int i = 0; i < need; i++) {
    ret[i] = (i & 1 ? fa[i >> 1].y : fa[i >> 1].x);
  }
  return ret;
}

vector<ll> convolution(const vector<ll>& a, const vector<ll>& b) {
  int n = len(a), m = len(b);
  if (!n || !m) return {};
  if (min(n, m) <= 2500) return convolution_naive(a, b);
  ll abs_sum_a = 0, abs_sum_b = 0;
  ll LIM = 1e15;
  FOR(i, n) abs_sum_a = min(LIM, abs_sum_a + abs(a[i]));
  FOR(i, m) abs_sum_b = min(LIM, abs_sum_b + abs(b[i]));
  if (i128(abs_sum_a) * abs_sum_b < 1e15) {
    vc<double> c = convolution_fft<ll>(a, b);
    vc<ll> res(len(c));
    FOR(i, len(c)) res[i] = ll(floor(c[i] + .5));
    return res;
  }

  static constexpr unsigned long long MOD1 = 754974721; // 2^24

  static constexpr unsigned long long MOD2 = 167772161; // 2^25

  static constexpr unsigned long long MOD3 = 469762049; // 2^26

  static constexpr unsigned long long M2M3 = MOD2 * MOD3;
  static constexpr unsigned long long M1M3 = MOD1 * MOD3;
  static constexpr unsigned long long M1M2 = MOD1 * MOD2;
  static constexpr unsigned long long M1M2M3 = MOD1 * MOD2 * MOD3;

  static const unsigned long long i1 = mod_inv(MOD2 * MOD3, MOD1);
  static const unsigned long long i2 = mod_inv(MOD1 * MOD3, MOD2);
  static const unsigned long long i3 = mod_inv(MOD1 * MOD2, MOD3);

  using mint1 = modint<MOD1>;
  using mint2 = modint<MOD2>;
  using mint3 = modint<MOD3>;

  vc<mint1> a1(n), b1(m);
  vc<mint2> a2(n), b2(m);
  vc<mint3> a3(n), b3(m);
  FOR(i, n) a1[i] = a[i], a2[i] = a[i], a3[i] = a[i];
  FOR(i, m) b1[i] = b[i], b2[i] = b[i], b3[i] = b[i];

  auto c1 = convolution_ntt<mint1>(a1, b1);
  auto c2 = convolution_ntt<mint2>(a2, b2);
  auto c3 = convolution_ntt<mint3>(a3, b3);

  vc<ll> c(n + m - 1);
  FOR(i, n + m - 1) {
    u64 x = 0;
    x += (c1[i].val * i1) % MOD1 * M2M3;
    x += (c2[i].val * i2) % MOD2 * M1M3;
    x += (c3[i].val * i3) % MOD3 * M1M2;
    ll diff = c1[i].val - ((long long)(x) % (long long)(MOD1));
    if (diff < 0) diff += MOD1;
    static constexpr unsigned long long offset[5]
        = {0, 0, M1M2M3, 2 * M1M2M3, 3 * M1M2M3};
    x -= offset[diff % 5];
    c[i] = x;
  }
  return c;
}

template <typename mint>
vc<mint> convolution(const vc<mint>& a, const vc<mint>& b) {
  int n = len(a), m = len(b);
  if (!n || !m) return {};
  if (mint::can_ntt()) {
    if (min(n, m) <= 50) return convolution_karatsuba<mint>(a, b);
    return convolution_ntt(a, b);
  }
  if (min(n, m) <= 200) return convolution_karatsuba<mint>(a, b);
  return convolution_garner(a, b);
}
#line 5 "poly/lagrange_interpolate_iota.hpp"

// Input: f(0), ..., f(n-1) and c. Return: f(c)

template <typename T, typename enable_if<has_mod<T>::value>::type * = nullptr>
T lagrange_interpolate_iota(vc<T> &f, T c) {
  int n = len(f);
  if (int(c.val) < n) return f[c.val];
  auto a = f;
  FOR(i, n) {
    a[i] = a[i] * fact_inv<T>(i) * fact_inv<T>(n - 1 - i);
    if ((n - 1 - i) & 1) a[i] = -a[i];
  }
  vc<T> lp(n + 1), rp(n + 1);
  lp[0] = rp[n] = 1;
  FOR(i, n) lp[i + 1] = lp[i] * (c - i);
  FOR_R(i, n) rp[i] = rp[i + 1] * (c - i);
  T ANS = 0;
  FOR(i, n) ANS += a[i] * lp[i] * rp[i + 1];
  return ANS;
}

// mod じゃない場合。かなり低次の多項式を想定している。O(n^2)

// Input: f(0), ..., f(n-1) and c. Return: f(c)

template <typename T, typename enable_if<!has_mod<T>::value>::type * = nullptr>
T lagrange_interpolate_iota(vc<T> &f, T c) {
  const int LIM = 10;
  int n = len(f);
  assert(n < LIM);

  // (-1)^{i-j} binom(i,j)

  static vvc<int> C;
  if (C.empty()) {
    C.assign(LIM, vc<int>(LIM));
    C[0][0] = 1;
    FOR(n, 1, LIM) FOR(k, n + 1) {
      C[n][k] += C[n - 1][k];
      if (k) C[n][k] += C[n - 1][k - 1];
    }
    FOR(n, LIM) FOR(k, n + 1) if ((n + k) % 2) C[n][k] = -C[n][k];
  }
  // f(x) = sum a_i binom(x,i)

  vc<T> a(n);
  FOR(i, n) FOR(j, i + 1) { a[i] += f[j] * C[i][j]; }

  T res = 0;
  T b = 1;
  FOR(i, n) {
    res += a[i] * b;
    b = b * (c - i) / (1 + i);
  }
  return res;
}

// Input: f(0), ..., f(n-1) and c, m

// Return: f(c), f(c+1), ..., f(c+m-1)

// Complexity: M(n, n + m)

template <typename mint>
vc<mint> lagrange_interpolate_iota(vc<mint> &f, mint c, int m) {
  if (m <= 60) {
    vc<mint> ANS(m);
    FOR(i, m) ANS[i] = lagrange_interpolate_iota(f, c + mint(i));
    return ANS;
  }
  ll n = len(f);
  auto a = f;
  FOR(i, n) {
    a[i] = a[i] * fact_inv<mint>(i) * fact_inv<mint>(n - 1 - i);
    if ((n - 1 - i) & 1) a[i] = -a[i];
  }
  // x = c, c+1, ... に対して a0/x + a1/(x-1) + ... を求めておく

  vc<mint> b(n + m - 1);
  FOR(i, n + m - 1) b[i] = mint(1) / (c + mint(i - n + 1));
  a = convolution(a, b);

  Sliding_Window_Aggregation<Monoid_Mul<mint>> swag;
  vc<mint> ANS(m);
  ll L = 0, R = 0;
  FOR(i, m) {
    while (L < i) { swag.pop(), ++L; }
    while (R - L < n) { swag.push(c + mint((R++) - n + 1)); }
    auto coef = swag.prod();
    if (coef == 0) {
      ANS[i] = f[(c + i).val];
    } else {
      ANS[i] = a[i + n - 1] * coef;
    }
  }
  return ANS;
}

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