CP-Algorithms Library
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cp-algo/math/convolution.hpp
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- Last update: 2025-12-10 02:23:10+01:00
- Include:
#include "cp-algo/math/convolution.hpp"
Depends on
cp-algo/math/common.hpp- cp-algo/math/cvector.hpp
- cp-algo/math/fft.hpp
- cp-algo/number_theory/modint.hpp
- cp-algo/random/rng.hpp
- cp-algo/util/big_alloc.hpp
- cp-algo/util/checkpoint.hpp
- cp-algo/util/complex.hpp
- cp-algo/util/simd.hpp
Required by
Code
#ifndef CP_ALGO_MATH_CONVOLUTION_HPP
#define CP_ALGO_MATH_CONVOLUTION_HPP
#include "fft.hpp"
#include "cvector.hpp"
#include <vector>
#include <algorithm>
#include <bit>
#include <type_traits>
#include <ranges>
namespace cp_algo::math {
// Convolution limited to the first `need` coefficients.
// Writes the result into `a`; performs in-place when possible (modint path).
template<class VecA, class VecB>
void convolution_prefix(VecA& a, VecB const& b, size_t need) {
using T = typename std::decay_t<VecA>::value_type;
size_t na = std::min(need, std::size(a));
size_t nb = std::min(need, std::size(b));
a.resize(na);
auto bv = b | std::views::take(nb);
if(na == 0 || nb == 0) {
a.clear();
return;
}
if constexpr (modint_type<T>) {
// Use NTT-based truncated multiplication. Works in-place on `a`.
fft::mul_truncate(a, bv, need);
} else if constexpr (std::is_same_v<T, fft::point>) {
size_t conv_len = na + nb - 1;
size_t n = std::bit_ceil(conv_len);
n = std::max(n, (size_t)fft::flen);
fft::cvector A(n), B(n);
for(size_t i = 0; i < na; i++) {
A.set(i, a[i]);
}
for(size_t i = 0; i < nb; i++) {
B.set(i, bv[i]);
}
A.fft();
B.fft();
A.dot(B);
A.ifft();
a.assign(need, T(0));
for(size_t i = 0; i < std::min(need, conv_len); i++) {
a[i] = A.template get<fft::point>(i);
}
} else if constexpr (std::is_same_v<T, fft::ftype>) {
// Imaginary-cyclic convolution modulo x^n-i to compute acyclic convolution
// Represents polynomials as point(a[i], a[i+n]) to work in x^n-i basis
size_t conv_len = na + nb - 1;
size_t n = std::bit_ceil(conv_len) / 2;
n = std::max(n, (size_t)fft::flen);
fft::cvector A(n), B(n);
// Pack as modulo x^n-i: A[i] = point(a[i], a[i+n])
for(size_t i = 0; i < std::min(n, na); i++) {
fft::ftype re = a[i], im = 0;
if(i + n < na) im = a[i + n];
A.set(i, fft::point(re, im));
}
for(size_t i = 0; i < std::min(n, nb); i++) {
fft::ftype re = bv[i], im = 0;
if(i + n < nb) im = bv[i + n];
B.set(i, fft::point(re, im));
}
A.fft();
B.fft();
A.dot(B);
A.ifft();
a.assign(2 * n, T(0));
for(size_t i = 0; i < n; i++) {
auto v = A.template get<fft::point>(i);
a[i] = v.real();
a[i + n] = v.imag();
}
a.resize(need);
} else {
// Generic fallback: use simple O(n^2) convolution from fft utilities.
fft::mul_slow(a, bv, need);
}
}
} // namespace cp_algo::math
#endif // CP_ALGO_MATH_CONVOLUTION_HPP
#line 1 "cp-algo/math/convolution.hpp"
#line 1 "cp-algo/math/fft.hpp"
#line 1 "cp-algo/number_theory/modint.hpp"
#line 1 "cp-algo/math/common.hpp"
#include <functional>
#include <cstdint>
#include <cassert>
namespace cp_algo::math {
#ifdef CP_ALGO_MAXN
const int maxn = CP_ALGO_MAXN;
#else
const int maxn = 1 << 19;
#endif
const int magic = 64; // threshold for sizes to run the naive algo
auto bpow(auto const& x, auto n, auto const& one, auto op) {
if(n == 0) {
return one;
} else {
auto t = bpow(x, n / 2, one, op);
t = op(t, t);
if(n % 2) {
t = op(t, x);
}
return t;
}
}
auto bpow(auto x, auto n, auto ans) {
return bpow(x, n, ans, std::multiplies{});
}
template<typename T>
T bpow(T const& x, auto n) {
return bpow(x, n, T(1));
}
inline constexpr auto inv2(auto x) {
assert(x % 2);
std::make_unsigned_t<decltype(x)> y = 1;
while(y * x != 1) {
y *= 2 - x * y;
}
return y;
}
}
#line 4 "cp-algo/number_theory/modint.hpp"
#include <iostream>
#line 6 "cp-algo/number_theory/modint.hpp"
namespace cp_algo::math {
template<typename modint, typename _Int>
struct modint_base {
using Int = _Int;
using UInt = std::make_unsigned_t<Int>;
static constexpr size_t bits = sizeof(Int) * 8;
using Int2 = std::conditional_t<bits <= 32, int64_t, __int128_t>;
using UInt2 = std::conditional_t<bits <= 32, uint64_t, __uint128_t>;
constexpr static Int mod() {
return modint::mod();
}
constexpr static Int remod() {
return modint::remod();
}
constexpr static UInt2 modmod() {
return UInt2(mod()) * mod();
}
constexpr modint_base() = default;
constexpr modint_base(Int2 rr) {
to_modint().setr(UInt((rr + modmod()) % mod()));
}
modint inv() const {
return bpow(to_modint(), mod() - 2);
}
modint operator - () const {
modint neg;
neg.r = std::min(-r, remod() - r);
return neg;
}
modint& operator /= (const modint &t) {
return to_modint() *= t.inv();
}
modint& operator *= (const modint &t) {
r = UInt(UInt2(r) * t.r % mod());
return to_modint();
}
modint& operator += (const modint &t) {
r += t.r; r = std::min(r, r - remod());
return to_modint();
}
modint& operator -= (const modint &t) {
r -= t.r; r = std::min(r, r + remod());
return to_modint();
}
modint operator + (const modint &t) const {return modint(to_modint()) += t;}
modint operator - (const modint &t) const {return modint(to_modint()) -= t;}
modint operator * (const modint &t) const {return modint(to_modint()) *= t;}
modint operator / (const modint &t) const {return modint(to_modint()) /= t;}
// Why <=> doesn't work?..
auto operator == (const modint &t) const {return to_modint().getr() == t.getr();}
auto operator != (const modint &t) const {return to_modint().getr() != t.getr();}
auto operator <= (const modint &t) const {return to_modint().getr() <= t.getr();}
auto operator >= (const modint &t) const {return to_modint().getr() >= t.getr();}
auto operator < (const modint &t) const {return to_modint().getr() < t.getr();}
auto operator > (const modint &t) const {return to_modint().getr() > t.getr();}
Int rem() const {
UInt R = to_modint().getr();
return R - (R > (UInt)mod() / 2) * mod();
}
constexpr void setr(UInt rr) {
r = rr;
}
constexpr UInt getr() const {
return r;
}
// Only use these if you really know what you're doing!
static UInt modmod8() {return UInt(8 * modmod());}
void add_unsafe(UInt t) {r += t;}
void pseudonormalize() {r = std::min(r, r - modmod8());}
modint const& normalize() {
if(r >= (UInt)mod()) {
r %= mod();
}
return to_modint();
}
void setr_direct(UInt rr) {r = rr;}
UInt getr_direct() const {return r;}
protected:
UInt r;
private:
constexpr modint& to_modint() {return static_cast<modint&>(*this);}
constexpr modint const& to_modint() const {return static_cast<modint const&>(*this);}
};
template<typename modint>
concept modint_type = std::is_base_of_v<modint_base<modint, typename modint::Int>, modint>;
template<modint_type modint>
decltype(std::cin)& operator >> (decltype(std::cin) &in, modint &x) {
typename modint::UInt r;
auto &res = in >> r;
x.setr(r);
return res;
}
template<modint_type modint>
decltype(std::cout)& operator << (decltype(std::cout) &out, modint const& x) {
return out << x.getr();
}
template<auto m>
struct modint: modint_base<modint<m>, decltype(m)> {
using Base = modint_base<modint<m>, decltype(m)>;
using Base::Base;
static constexpr Base::Int mod() {return m;}
static constexpr Base::UInt remod() {return m;}
auto getr() const {return Base::r;}
};
template<typename Int = int>
struct dynamic_modint: modint_base<dynamic_modint<Int>, Int> {
using Base = modint_base<dynamic_modint<Int>, Int>;
using Base::Base;
static Base::UInt m_reduce(Base::UInt2 ab) {
if(mod() % 2 == 0) [[unlikely]] {
return typename Base::UInt(ab % mod());
} else {
typename Base::UInt2 m = typename Base::UInt(ab) * imod();
return typename Base::UInt((ab + m * mod()) >> Base::bits);
}
}
static Base::UInt m_transform(Base::UInt a) {
if(mod() % 2 == 0) [[unlikely]] {
return a;
} else {
return m_reduce(a * pw128());
}
}
dynamic_modint& operator *= (const dynamic_modint &t) {
Base::r = m_reduce(typename Base::UInt2(Base::r) * t.r);
return *this;
}
void setr(Base::UInt rr) {
Base::r = m_transform(rr);
}
Base::UInt getr() const {
typename Base::UInt res = m_reduce(Base::r);
return std::min(res, res - mod());
}
static Int mod() {return m;}
static Int remod() {return 2 * m;}
static Base::UInt imod() {return im;}
static Base::UInt2 pw128() {return r2;}
static void switch_mod(Int nm) {
m = nm;
im = m % 2 ? inv2(-m) : 0;
r2 = static_cast<Base::UInt>(static_cast<Base::UInt2>(-1) % m + 1);
}
// Wrapper for temp switching
auto static with_mod(Int tmp, auto callback) {
struct scoped {
Int prev = mod();
~scoped() {switch_mod(prev);}
} _;
switch_mod(tmp);
return callback();
}
private:
static thread_local Int m;
static thread_local Base::UInt im, r2;
};
template<typename Int>
Int thread_local dynamic_modint<Int>::m = 1;
template<typename Int>
dynamic_modint<Int>::Base::UInt thread_local dynamic_modint<Int>::im = -1;
template<typename Int>
dynamic_modint<Int>::Base::UInt thread_local dynamic_modint<Int>::r2 = 0;
}
#line 1 "cp-algo/util/checkpoint.hpp"
#line 1 "cp-algo/util/big_alloc.hpp"
#include <map>
#include <deque>
#include <vector>
#include <string>
#include <cstddef>
#line 10 "cp-algo/util/big_alloc.hpp"
// Single macro to detect POSIX platforms (Linux, Unix, macOS)
#if defined(__linux__) || defined(__unix__) || (defined(__APPLE__) && defined(__MACH__))
# define CP_ALGO_USE_MMAP 1
# include <sys/mman.h>
#else
# define CP_ALGO_USE_MMAP 0
#endif
namespace cp_algo {
template <typename T, std::size_t Align = 32>
class big_alloc {
static_assert( Align >= alignof(void*), "Align must be at least pointer-size");
static_assert(std::popcount(Align) == 1, "Align must be a power of two");
public:
using value_type = T;
template <class U> struct rebind { using other = big_alloc<U, Align>; };
constexpr bool operator==(const big_alloc&) const = default;
constexpr bool operator!=(const big_alloc&) const = default;
big_alloc() noexcept = default;
template <typename U, std::size_t A>
big_alloc(const big_alloc<U, A>&) noexcept {}
[[nodiscard]] T* allocate(std::size_t n) {
std::size_t padded = round_up(n * sizeof(T));
std::size_t align = std::max<std::size_t>(alignof(T), Align);
#if CP_ALGO_USE_MMAP
if (padded >= MEGABYTE) {
void* raw = mmap(nullptr, padded,
PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
madvise(raw, padded, MADV_HUGEPAGE);
madvise(raw, padded, MADV_POPULATE_WRITE);
return static_cast<T*>(raw);
}
#endif
return static_cast<T*>(::operator new(padded, std::align_val_t(align)));
}
void deallocate(T* p, std::size_t n) noexcept {
if (!p) return;
std::size_t padded = round_up(n * sizeof(T));
std::size_t align = std::max<std::size_t>(alignof(T), Align);
#if CP_ALGO_USE_MMAP
if (padded >= MEGABYTE) { munmap(p, padded); return; }
#endif
::operator delete(p, padded, std::align_val_t(align));
}
private:
static constexpr std::size_t MEGABYTE = 1 << 20;
static constexpr std::size_t round_up(std::size_t x) noexcept {
return (x + Align - 1) / Align * Align;
}
};
template<typename T>
using big_vector = std::vector<T, big_alloc<T>>;
template<typename T>
using big_basic_string = std::basic_string<T, std::char_traits<T>, big_alloc<T>>;
template<typename T>
using big_deque = std::deque<T, big_alloc<T>>;
template<typename Key, typename Value, typename Compare = std::less<Key>>
using big_map = std::map<Key, Value, Compare, big_alloc<std::pair<const Key, Value>>>;
using big_string = big_basic_string<char>;
}
#line 5 "cp-algo/util/checkpoint.hpp"
#include <chrono>
#line 8 "cp-algo/util/checkpoint.hpp"
namespace cp_algo {
#ifdef CP_ALGO_CHECKPOINT
big_map<big_string, double> checkpoints;
double last;
#endif
template<bool final = false>
void checkpoint([[maybe_unused]] auto const& _msg) {
#ifdef CP_ALGO_CHECKPOINT
big_string msg = _msg;
double now = (double)clock() / CLOCKS_PER_SEC;
double delta = now - last;
last = now;
if(msg.size() && !final) {
checkpoints[msg] += delta;
}
if(final) {
for(auto const& [key, value] : checkpoints) {
std::cerr << key << ": " << value * 1000 << " ms\n";
}
std::cerr << "Total: " << now * 1000 << " ms\n";
}
#endif
}
template<bool final = false>
void checkpoint() {
checkpoint<final>("");
}
}
#line 1 "cp-algo/random/rng.hpp"
#line 4 "cp-algo/random/rng.hpp"
#include <random>
namespace cp_algo::random {
std::mt19937_64 gen(
std::chrono::steady_clock::now().time_since_epoch().count()
);
uint64_t rng() {
return gen();
}
}
#line 1 "cp-algo/math/cvector.hpp"
#line 1 "cp-algo/util/simd.hpp"
#include <experimental/simd>
#line 6 "cp-algo/util/simd.hpp"
#include <memory>
#if defined(__x86_64__) && !defined(CP_ALGO_DISABLE_AVX2)
#define CP_ALGO_SIMD_AVX2_TARGET _Pragma("GCC target(\"avx2\")")
#else
#define CP_ALGO_SIMD_AVX2_TARGET
#endif
#define CP_ALGO_SIMD_PRAGMA_PUSH \
_Pragma("GCC push_options") \
_Pragma("GCC optimize(\"O3,unroll-loops\")") \
CP_ALGO_SIMD_AVX2_TARGET
CP_ALGO_SIMD_PRAGMA_PUSH
namespace cp_algo {
template<typename T, size_t len>
using simd [[gnu::vector_size(len * sizeof(T))]] = T;
using i64x4 = simd<int64_t, 4>;
using u64x4 = simd<uint64_t, 4>;
using u32x8 = simd<uint32_t, 8>;
using i32x4 = simd<int32_t, 4>;
using u32x4 = simd<uint32_t, 4>;
using i16x4 = simd<int16_t, 4>;
using u8x32 = simd<uint8_t, 32>;
using dx4 = simd<double, 4>;
dx4 abs(dx4 a) {
return dx4{
std::abs(a[0]),
std::abs(a[1]),
std::abs(a[2]),
std::abs(a[3])
};
}
// https://stackoverflow.com/a/77376595
// works for ints in (-2^51, 2^51)
static constexpr dx4 magic = dx4() + (3ULL << 51);
inline i64x4 lround(dx4 x) {
return i64x4(x + magic) - i64x4(magic);
}
inline dx4 to_double(i64x4 x) {
return dx4(x + i64x4(magic)) - magic;
}
inline dx4 round(dx4 a) {
return dx4{
std::nearbyint(a[0]),
std::nearbyint(a[1]),
std::nearbyint(a[2]),
std::nearbyint(a[3])
};
}
inline u64x4 low32(u64x4 x) {
return x & uint32_t(-1);
}
inline auto swap_bytes(auto x) {
return decltype(x)(__builtin_shufflevector(u32x8(x), u32x8(x), 1, 0, 3, 2, 5, 4, 7, 6));
}
inline u64x4 montgomery_reduce(u64x4 x, uint32_t mod, uint32_t imod) {
#ifdef __AVX2__
auto x_ninv = u64x4(_mm256_mul_epu32(__m256i(x), __m256i() + imod));
x += u64x4(_mm256_mul_epu32(__m256i(x_ninv), __m256i() + mod));
#else
auto x_ninv = u64x4(u32x8(low32(x)) * imod);
x += x_ninv * uint64_t(mod);
#endif
return swap_bytes(x);
}
inline u64x4 montgomery_mul(u64x4 x, u64x4 y, uint32_t mod, uint32_t imod) {
#ifdef __AVX2__
return montgomery_reduce(u64x4(_mm256_mul_epu32(__m256i(x), __m256i(y))), mod, imod);
#else
return montgomery_reduce(x * y, mod, imod);
#endif
}
inline u32x8 montgomery_mul(u32x8 x, u32x8 y, uint32_t mod, uint32_t imod) {
return u32x8(montgomery_mul(u64x4(x), u64x4(y), mod, imod)) |
u32x8(swap_bytes(montgomery_mul(u64x4(swap_bytes(x)), u64x4(swap_bytes(y)), mod, imod)));
}
inline dx4 rotate_right(dx4 x) {
static constexpr u64x4 shuffler = {3, 0, 1, 2};
return __builtin_shuffle(x, shuffler);
}
template<std::size_t Align = 32>
inline bool is_aligned(const auto* p) noexcept {
return (reinterpret_cast<std::uintptr_t>(p) % Align) == 0;
}
template<class Target>
inline Target& vector_cast(auto &&p) {
return *reinterpret_cast<Target*>(std::assume_aligned<alignof(Target)>(&p));
}
}
#pragma GCC pop_options
#line 1 "cp-algo/util/complex.hpp"
#line 4 "cp-algo/util/complex.hpp"
#include <cmath>
#include <type_traits>
#line 7 "cp-algo/util/complex.hpp"
CP_ALGO_SIMD_PRAGMA_PUSH
namespace cp_algo {
// Custom implementation, since std::complex is UB on non-floating types
template<typename T>
struct complex {
using value_type = T;
T x, y;
inline constexpr complex(): x(), y() {}
inline constexpr complex(T const& x): x(x), y() {}
inline constexpr complex(T const& x, T const& y): x(x), y(y) {}
inline complex& operator *= (T const& t) {x *= t; y *= t; return *this;}
inline complex& operator /= (T const& t) {x /= t; y /= t; return *this;}
inline complex operator * (T const& t) const {return complex(*this) *= t;}
inline complex operator / (T const& t) const {return complex(*this) /= t;}
inline complex& operator += (complex const& t) {x += t.x; y += t.y; return *this;}
inline complex& operator -= (complex const& t) {x -= t.x; y -= t.y; return *this;}
inline complex operator * (complex const& t) const {return {x * t.x - y * t.y, x * t.y + y * t.x};}
inline complex operator / (complex const& t) const {return *this * t.conj() / t.norm();}
inline complex operator + (complex const& t) const {return complex(*this) += t;}
inline complex operator - (complex const& t) const {return complex(*this) -= t;}
inline complex& operator *= (complex const& t) {return *this = *this * t;}
inline complex& operator /= (complex const& t) {return *this = *this / t;}
inline complex operator - () const {return {-x, -y};}
inline complex conj() const {return {x, -y};}
inline T norm() const {return x * x + y * y;}
inline T abs() const {return std::sqrt(norm());}
inline T const real() const {return x;}
inline T const imag() const {return y;}
inline T& real() {return x;}
inline T& imag() {return y;}
inline static constexpr complex polar(T r, T theta) {return {T(r * cos(theta)), T(r * sin(theta))};}
inline auto operator <=> (complex const& t) const = default;
};
template<typename T> inline complex<T> conj(complex<T> const& x) {return x.conj();}
template<typename T> inline T norm(complex<T> const& x) {return x.norm();}
template<typename T> inline T abs(complex<T> const& x) {return x.abs();}
template<typename T> inline T& real(complex<T> &x) {return x.real();}
template<typename T> inline T& imag(complex<T> &x) {return x.imag();}
template<typename T> inline T const real(complex<T> const& x) {return x.real();}
template<typename T> inline T const imag(complex<T> const& x) {return x.imag();}
template<typename T>
inline constexpr complex<T> polar(T r, T theta) {
return complex<T>::polar(r, theta);
}
template<typename T>
inline std::ostream& operator << (std::ostream &out, complex<T> const& x) {
return out << x.real() << ' ' << x.imag();
}
}
#pragma GCC pop_options
#line 7 "cp-algo/math/cvector.hpp"
#include <ranges>
#include <bit>
CP_ALGO_SIMD_PRAGMA_PUSH
namespace stdx = std::experimental;
namespace cp_algo::math::fft {
static constexpr size_t flen = 4;
using ftype = double;
using vftype = dx4;
using point = complex<ftype>;
using vpoint = complex<vftype>;
static constexpr vftype vz = {};
vpoint vi(vpoint const& r) {
return {-imag(r), real(r)};
}
struct cvector {
big_vector<vpoint> r;
cvector(size_t n) {
n = std::max(flen, std::bit_ceil(n));
r.resize(n / flen);
checkpoint("cvector create");
}
vpoint& at(size_t k) {return r[k / flen];}
vpoint at(size_t k) const {return r[k / flen];}
template<class pt = point>
inline void set(size_t k, pt const& t) {
if constexpr(std::is_same_v<pt, point>) {
real(r[k / flen])[k % flen] = real(t);
imag(r[k / flen])[k % flen] = imag(t);
} else {
at(k) = t;
}
}
template<class pt = point>
inline pt get(size_t k) const {
if constexpr(std::is_same_v<pt, point>) {
return {real(r[k / flen])[k % flen], imag(r[k / flen])[k % flen]};
} else {
return at(k);
}
}
size_t size() const {
return flen * r.size();
}
static constexpr size_t eval_arg(size_t n) {
if(n < pre_evals) {
return eval_args[n];
} else {
return eval_arg(n / 2) | (n & 1) << (std::bit_width(n) - 1);
}
}
static constexpr point eval_point(size_t n) {
if(n % 2) {
return -eval_point(n - 1);
} else if(n % 4) {
return eval_point(n - 2) * point(0, 1);
} else if(n / 4 < pre_evals) {
return evalp[n / 4];
} else {
return polar<ftype>(1., std::numbers::pi / (ftype)std::bit_floor(n) * (ftype)eval_arg(n));
}
}
static constexpr std::array<point, 32> roots = []() {
std::array<point, 32> res;
for(size_t i = 2; i < 32; i++) {
res[i] = polar<ftype>(1., std::numbers::pi / (1ull << (i - 2)));
}
return res;
}();
static constexpr point root(size_t n) {
return roots[std::bit_width(n)];
}
template<int step>
static void exec_on_eval(size_t n, size_t k, auto &&callback) {
callback(k, root(4 * step * n) * eval_point(step * k));
}
template<int step>
static void exec_on_evals(size_t n, auto &&callback) {
point factor = root(4 * step * n);
for(size_t i = 0; i < n; i++) {
callback(i, factor * eval_point(step * i));
}
}
static void do_dot_iter(point rt, vpoint& Bv, vpoint const& Av, vpoint& res) {
res += Av * Bv;
real(Bv) = rotate_right(real(Bv));
imag(Bv) = rotate_right(imag(Bv));
auto x = real(Bv)[0], y = imag(Bv)[0];
real(Bv)[0] = x * real(rt) - y * imag(rt);
imag(Bv)[0] = x * imag(rt) + y * real(rt);
}
void dot(cvector const& t) {
size_t n = this->size();
exec_on_evals<1>(n / flen, [&](size_t k, point rt) __attribute__((always_inline)) {
k *= flen;
auto [Ax, Ay] = at(k);
auto Bv = t.at(k);
vpoint res = vz;
for (size_t i = 0; i < flen; i++) {
vpoint Av = vpoint(vz + Ax[i], vz + Ay[i]);
do_dot_iter(rt, Bv, Av, res);
}
set(k, res);
});
checkpoint("dot");
}
template<bool partial = true>
void ifft() {
size_t n = size();
if constexpr (!partial) {
point pi(0, 1);
exec_on_evals<4>(n / 4, [&](size_t k, point rt) __attribute__((always_inline)) {
k *= 4;
point v1 = conj(rt);
point v2 = v1 * v1;
point v3 = v1 * v2;
auto A = get(k);
auto B = get(k + 1);
auto C = get(k + 2);
auto D = get(k + 3);
set(k, (A + B) + (C + D));
set(k + 2, ((A + B) - (C + D)) * v2);
set(k + 1, ((A - B) - pi * (C - D)) * v1);
set(k + 3, ((A - B) + pi * (C - D)) * v3);
});
}
bool parity = std::countr_zero(n) % 2;
if(parity) {
exec_on_evals<2>(n / (2 * flen), [&](size_t k, point rt) __attribute__((always_inline)) {
k *= 2 * flen;
vpoint cvrt = {vz + real(rt), vz - imag(rt)};
auto B = at(k) - at(k + flen);
at(k) += at(k + flen);
at(k + flen) = B * cvrt;
});
}
for(size_t leaf = 3 * flen; leaf < n; leaf += 4 * flen) {
size_t level = std::countr_one(leaf + 3);
for(size_t lvl = 4 + parity; lvl <= level; lvl += 2) {
size_t i = (1 << lvl) / 4;
exec_on_eval<4>(n >> lvl, leaf >> lvl, [&](size_t k, point rt) __attribute__((always_inline)) {
k <<= lvl;
vpoint v1 = {vz + real(rt), vz - imag(rt)};
vpoint v2 = v1 * v1;
vpoint v3 = v1 * v2;
for(size_t j = k; j < k + i; j += flen) {
auto A = at(j);
auto B = at(j + i);
auto C = at(j + 2 * i);
auto D = at(j + 3 * i);
at(j) = ((A + B) + (C + D));
at(j + 2 * i) = ((A + B) - (C + D)) * v2;
at(j + i) = ((A - B) - vi(C - D)) * v1;
at(j + 3 * i) = ((A - B) + vi(C - D)) * v3;
}
});
}
}
checkpoint("ifft");
for(size_t k = 0; k < n; k += flen) {
if constexpr (partial) {
set(k, get<vpoint>(k) /= vz + ftype(n / flen));
} else {
set(k, get<vpoint>(k) /= vz + ftype(n));
}
}
}
template<bool partial = true>
void fft() {
size_t n = size();
bool parity = std::countr_zero(n) % 2;
for(size_t leaf = 0; leaf < n; leaf += 4 * flen) {
size_t level = std::countr_zero(n + leaf);
level -= level % 2 != parity;
for(size_t lvl = level; lvl >= 4; lvl -= 2) {
size_t i = (1 << lvl) / 4;
exec_on_eval<4>(n >> lvl, leaf >> lvl, [&](size_t k, point rt) __attribute__((always_inline)) {
k <<= lvl;
vpoint v1 = {vz + real(rt), vz + imag(rt)};
vpoint v2 = v1 * v1;
vpoint v3 = v1 * v2;
for(size_t j = k; j < k + i; j += flen) {
auto A = at(j);
auto B = at(j + i) * v1;
auto C = at(j + 2 * i) * v2;
auto D = at(j + 3 * i) * v3;
at(j) = (A + C) + (B + D);
at(j + i) = (A + C) - (B + D);
at(j + 2 * i) = (A - C) + vi(B - D);
at(j + 3 * i) = (A - C) - vi(B - D);
}
});
}
}
if(parity) {
exec_on_evals<2>(n / (2 * flen), [&](size_t k, point rt) __attribute__((always_inline)) {
k *= 2 * flen;
vpoint vrt = {vz + real(rt), vz + imag(rt)};
auto t = at(k + flen) * vrt;
at(k + flen) = at(k) - t;
at(k) += t;
});
}
if constexpr (!partial) {
point pi(0, 1);
exec_on_evals<4>(n / 4, [&](size_t k, point rt) __attribute__((always_inline)) {
k *= 4;
point v1 = rt;
point v2 = v1 * v1;
point v3 = v1 * v2;
auto A = get(k);
auto B = get(k + 1) * v1;
auto C = get(k + 2) * v2;
auto D = get(k + 3) * v3;
set(k, (A + C) + (B + D));
set(k + 1, (A + C) - (B + D));
set(k + 2, (A - C) + pi * (B - D));
set(k + 3, (A - C) - pi * (B - D));
});
}
checkpoint("fft");
}
static constexpr size_t pre_evals = 1 << 16;
static const std::array<size_t, pre_evals> eval_args;
static const std::array<point, pre_evals> evalp;
};
const std::array<size_t, cvector::pre_evals> cvector::eval_args = []() {
std::array<size_t, pre_evals> res = {};
for(size_t i = 1; i < pre_evals; i++) {
res[i] = res[i >> 1] | (i & 1) << (std::bit_width(i) - 1);
}
return res;
}();
const std::array<point, cvector::pre_evals> cvector::evalp = []() {
std::array<point, pre_evals> res = {};
res[0] = 1;
for(size_t n = 1; n < pre_evals; n++) {
res[n] = polar<ftype>(1., std::numbers::pi * ftype(eval_args[n]) / ftype(4 * std::bit_floor(n)));
}
return res;
}();
}
#pragma GCC pop_options
#line 9 "cp-algo/math/fft.hpp"
CP_ALGO_SIMD_PRAGMA_PUSH
namespace cp_algo::math::fft {
template<modint_type base>
struct dft {
cvector A, B;
static base factor, ifactor;
using Int2 = base::Int2;
static bool _init;
static int split() {
static const int splt = int(std::sqrt(base::mod())) + 1;
return splt;
}
static uint32_t mod, imod;
static void init() {
if(!_init) {
factor = 1 + random::rng() % (base::mod() - 1);
ifactor = base(1) / factor;
mod = base::mod();
imod = -inv2<uint32_t>(base::mod());
_init = true;
}
}
static std::pair<vftype, vftype>
do_split(auto const& a, size_t idx, u64x4 mul) {
if(idx >= std::size(a)) {
return std::pair{vftype(), vftype()};
}
u64x4 au = {
idx < std::size(a) ? a[idx].getr() : 0,
idx + 1 < std::size(a) ? a[idx + 1].getr() : 0,
idx + 2 < std::size(a) ? a[idx + 2].getr() : 0,
idx + 3 < std::size(a) ? a[idx + 3].getr() : 0
};
au = montgomery_mul(au, mul, mod, imod);
au = au >= base::mod() ? au - base::mod() : au;
auto ai = to_double(i64x4(au >= base::mod() / 2 ? au - base::mod() : au));
auto quo = round(ai / split());
return std::pair{ai - quo * split(), quo};
}
dft(size_t n): A(n), B(n) {init();}
dft(auto const& a, size_t n, bool partial = true): A(n), B(n) {
init();
base b2x32 = bpow(base(2), 32);
u64x4 cur = {
(bpow(factor, 1) * b2x32).getr(),
(bpow(factor, 2) * b2x32).getr(),
(bpow(factor, 3) * b2x32).getr(),
(bpow(factor, 4) * b2x32).getr()
};
u64x4 step4 = u64x4{} + (bpow(factor, 4) * b2x32).getr();
u64x4 stepn = u64x4{} + (bpow(factor, n) * b2x32).getr();
for(size_t i = 0; i < std::min(n, std::size(a)); i += flen) {
auto [rai, qai] = do_split(a, i, cur);
auto [rani, qani] = do_split(a, n + i, montgomery_mul(cur, stepn, mod, imod));
A.at(i) = vpoint(rai, rani);
B.at(i) = vpoint(qai, qani);
cur = montgomery_mul(cur, step4, mod, imod);
}
checkpoint("dft init");
if(n) {
if(partial) {
A.fft();
B.fft();
} else {
A.template fft<false>();
B.template fft<false>();
}
}
}
static void do_dot_iter(point rt, vpoint& Cv, vpoint& Dv, vpoint const& Av, vpoint const& Bv, vpoint& AC, vpoint& AD, vpoint& BC, vpoint& BD) {
AC += Av * Cv; AD += Av * Dv;
BC += Bv * Cv; BD += Bv * Dv;
real(Cv) = rotate_right(real(Cv));
imag(Cv) = rotate_right(imag(Cv));
real(Dv) = rotate_right(real(Dv));
imag(Dv) = rotate_right(imag(Dv));
auto cx = real(Cv)[0], cy = imag(Cv)[0];
auto dx = real(Dv)[0], dy = imag(Dv)[0];
real(Cv)[0] = cx * real(rt) - cy * imag(rt);
imag(Cv)[0] = cx * imag(rt) + cy * real(rt);
real(Dv)[0] = dx * real(rt) - dy * imag(rt);
imag(Dv)[0] = dx * imag(rt) + dy * real(rt);
}
template<bool overwrite = true, bool partial = true>
void dot(auto const& C, auto const& D, auto &Aout, auto &Bout, auto &Cout) const {
cvector::exec_on_evals<1>(A.size() / flen, [&](size_t k, point rt) __attribute__((always_inline)) {
k *= flen;
vpoint AC, AD, BC, BD;
AC = AD = BC = BD = vz;
auto Cv = C.at(k), Dv = D.at(k);
if constexpr(partial) {
auto [Ax, Ay] = A.at(k);
auto [Bx, By] = B.at(k);
for (size_t i = 0; i < flen; i++) {
vpoint Av = {vz + Ax[i], vz + Ay[i]}, Bv = {vz + Bx[i], vz + By[i]};
do_dot_iter(rt, Cv, Dv, Av, Bv, AC, AD, BC, BD);
}
} else {
AC = A.at(k) * Cv;
AD = A.at(k) * Dv;
BC = B.at(k) * Cv;
BD = B.at(k) * Dv;
}
if constexpr (overwrite) {
Aout.at(k) = AC;
Cout.at(k) = AD + BC;
Bout.at(k) = BD;
} else {
Aout.at(k) += AC;
Cout.at(k) += AD + BC;
Bout.at(k) += BD;
}
});
checkpoint("dot");
}
void dot(auto &&C, auto const& D) {
dot(C, D, A, B, C);
}
static void do_recover_iter(size_t idx, auto A, auto B, auto C, auto mul, uint64_t splitsplit, auto &res) {
auto A0 = lround(A), A1 = lround(C), A2 = lround(B);
auto Ai = A0 + A1 * split() + A2 * splitsplit + uint64_t(base::modmod());
auto Au = montgomery_reduce(u64x4(Ai), mod, imod);
Au = montgomery_mul(Au, mul, mod, imod);
Au = Au >= base::mod() ? Au - base::mod() : Au;
for(size_t j = 0; j < flen; j++) {
res[idx + j].setr(typename base::UInt(Au[j]));
}
}
void recover_mod(auto &&C, auto &res, size_t k) {
size_t check = (k + flen - 1) / flen * flen;
assert(res.size() >= check);
size_t n = A.size();
auto const splitsplit = base(split() * split()).getr();
base b2x32 = bpow(base(2), 32);
base b2x64 = bpow(base(2), 64);
u64x4 cur = {
(bpow(ifactor, 2) * b2x64).getr(),
(bpow(ifactor, 3) * b2x64).getr(),
(bpow(ifactor, 4) * b2x64).getr(),
(bpow(ifactor, 5) * b2x64).getr()
};
u64x4 step4 = u64x4{} + (bpow(ifactor, 4) * b2x32).getr();
u64x4 stepn = u64x4{} + (bpow(ifactor, n) * b2x32).getr();
for(size_t i = 0; i < std::min(n, k); i += flen) {
auto [Ax, Ay] = A.at(i);
auto [Bx, By] = B.at(i);
auto [Cx, Cy] = C.at(i);
do_recover_iter(i, Ax, Bx, Cx, cur, splitsplit, res);
if(i + n < k) {
do_recover_iter(i + n, Ay, By, Cy, montgomery_mul(cur, stepn, mod, imod), splitsplit, res);
}
cur = montgomery_mul(cur, step4, mod, imod);
}
checkpoint("recover mod");
}
void mul(auto &&C, auto const& D, auto &res, size_t k) {
assert(A.size() == C.size());
size_t n = A.size();
if(!n) {
res = {};
return;
}
dot(C, D);
A.ifft();
B.ifft();
C.ifft();
recover_mod(C, res, k);
}
void mul_inplace(auto &&B, auto& res, size_t k) {
mul(B.A, B.B, res, k);
}
void mul(auto const& B, auto& res, size_t k) {
mul(cvector(B.A), B.B, res, k);
}
big_vector<base> operator *= (dft &B) {
big_vector<base> res(2 * A.size());
mul_inplace(B, res, 2 * A.size());
return res;
}
big_vector<base> operator *= (dft const& B) {
big_vector<base> res(2 * A.size());
mul(B, res, 2 * A.size());
return res;
}
auto operator * (dft const& B) const {
return dft(*this) *= B;
}
point operator [](int i) const {return A.get(i);}
};
template<modint_type base> base dft<base>::factor = 1;
template<modint_type base> base dft<base>::ifactor = 1;
template<modint_type base> bool dft<base>::_init = false;
template<modint_type base> uint32_t dft<base>::mod = {};
template<modint_type base> uint32_t dft<base>::imod = {};
void mul_slow(auto &a, auto const& b, size_t k) {
if(std::empty(a) || std::empty(b)) {
a.clear();
} else {
size_t n = std::min(k, std::size(a));
size_t m = std::min(k, std::size(b));
a.resize(k);
for(int j = int(k - 1); j >= 0; j--) {
a[j] *= b[0];
for(int i = std::max(j - (int)n, 0) + 1; i < std::min(j + 1, (int)m); i++) {
a[j] += a[j - i] * b[i];
}
}
}
}
size_t com_size(size_t as, size_t bs) {
if(!as || !bs) {
return 0;
}
return std::max(flen, std::bit_ceil(as + bs - 1) / 2);
}
void mul_truncate(auto &a, auto const& b, size_t k) {
using base = std::decay_t<decltype(a[0])>;
if(std::min({k, std::size(a), std::size(b)}) < magic) {
mul_slow(a, b, k);
return;
}
auto n = std::max(flen, std::bit_ceil(
std::min(k, std::size(a)) + std::min(k, std::size(b)) - 1
) / 2);
auto A = dft<base>(a | std::views::take(k), n);
auto B = dft<base>(b | std::views::take(k), n);
a.resize((k + flen - 1) / flen * flen);
A.mul_inplace(B, a, k);
a.resize(k);
}
// store mod x^n-k in first half, x^n+k in second half
void mod_split(auto &&x, size_t n, auto k) {
using base = std::decay_t<decltype(k)>;
dft<base>::init();
assert(std::size(x) == 2 * n);
u64x4 cur = u64x4{} + (k * bpow(base(2), 32)).getr();
for(size_t i = 0; i < n; i += flen) {
u64x4 xl = {
x[i].getr(),
x[i + 1].getr(),
x[i + 2].getr(),
x[i + 3].getr()
};
u64x4 xr = {
x[n + i].getr(),
x[n + i + 1].getr(),
x[n + i + 2].getr(),
x[n + i + 3].getr()
};
xr = montgomery_mul(xr, cur, dft<base>::mod, dft<base>::imod);
xr = xr >= base::mod() ? xr - base::mod() : xr;
auto t = xr;
xr = xl - t;
xl += t;
xl = xl >= base::mod() ? xl - base::mod() : xl;
xr = xr >= base::mod() ? xr + base::mod() : xr;
for(size_t k = 0; k < flen; k++) {
x[i + k].setr(typename base::UInt(xl[k]));
x[n + i + k].setr(typename base::UInt(xr[k]));
}
}
cp_algo::checkpoint("mod split");
}
void cyclic_mul(auto &a, auto &&b, size_t k) {
assert(std::popcount(k) == 1);
assert(std::size(a) == std::size(b) && std::size(a) == k);
using base = std::decay_t<decltype(a[0])>;
dft<base>::init();
if(k <= (1 << 16)) {
big_vector<base> ap(begin(a), end(a));
mul_truncate(ap, b, 2 * k);
mod_split(ap, k, bpow(dft<base>::factor, k));
std::ranges::copy(ap | std::views::take(k), begin(a));
return;
}
k /= 2;
auto factor = bpow(dft<base>::factor, k);
mod_split(a, k, factor);
mod_split(b, k, factor);
auto la = std::span(a).first(k);
auto lb = std::span(b).first(k);
auto ra = std::span(a).last(k);
auto rb = std::span(b).last(k);
cyclic_mul(la, lb, k);
auto A = dft<base>(ra, k / 2);
auto B = dft<base>(rb, k / 2);
A.mul_inplace(B, ra, k);
base i2 = base(2).inv();
factor = factor.inv() * i2;
for(size_t i = 0; i < k; i++) {
auto t = (a[i] + a[i + k]) * i2;
a[i + k] = (a[i] - a[i + k]) * factor;
a[i] = t;
}
cp_algo::checkpoint("mod join");
}
auto make_copy(auto &&x) {
return x;
}
void cyclic_mul(auto &a, auto const& b, size_t k) {
return cyclic_mul(a, make_copy(b), k);
}
void mul(auto &a, auto &&b) {
size_t N = size(a) + size(b);
if(N > (1 << 20)) {
N--;
size_t NN = std::bit_ceil(N);
a.resize(NN);
b.resize(NN);
cyclic_mul(a, b, NN);
a.resize(N);
} else {
mul_truncate(a, b, N - 1);
}
}
void mul(auto &a, auto const& b) {
size_t N = size(a) + size(b);
if(N > (1 << 20)) {
mul(a, make_copy(b));
} else {
mul_truncate(a, b, N - 1);
}
}
}
#pragma GCC pop_options
#line 6 "cp-algo/math/convolution.hpp"
#include <algorithm>
#line 10 "cp-algo/math/convolution.hpp"
namespace cp_algo::math {
// Convolution limited to the first `need` coefficients.
// Writes the result into `a`; performs in-place when possible (modint path).
template<class VecA, class VecB>
void convolution_prefix(VecA& a, VecB const& b, size_t need) {
using T = typename std::decay_t<VecA>::value_type;
size_t na = std::min(need, std::size(a));
size_t nb = std::min(need, std::size(b));
a.resize(na);
auto bv = b | std::views::take(nb);
if(na == 0 || nb == 0) {
a.clear();
return;
}
if constexpr (modint_type<T>) {
// Use NTT-based truncated multiplication. Works in-place on `a`.
fft::mul_truncate(a, bv, need);
} else if constexpr (std::is_same_v<T, fft::point>) {
size_t conv_len = na + nb - 1;
size_t n = std::bit_ceil(conv_len);
n = std::max(n, (size_t)fft::flen);
fft::cvector A(n), B(n);
for(size_t i = 0; i < na; i++) {
A.set(i, a[i]);
}
for(size_t i = 0; i < nb; i++) {
B.set(i, bv[i]);
}
A.fft();
B.fft();
A.dot(B);
A.ifft();
a.assign(need, T(0));
for(size_t i = 0; i < std::min(need, conv_len); i++) {
a[i] = A.template get<fft::point>(i);
}
} else if constexpr (std::is_same_v<T, fft::ftype>) {
// Imaginary-cyclic convolution modulo x^n-i to compute acyclic convolution
// Represents polynomials as point(a[i], a[i+n]) to work in x^n-i basis
size_t conv_len = na + nb - 1;
size_t n = std::bit_ceil(conv_len) / 2;
n = std::max(n, (size_t)fft::flen);
fft::cvector A(n), B(n);
// Pack as modulo x^n-i: A[i] = point(a[i], a[i+n])
for(size_t i = 0; i < std::min(n, na); i++) {
fft::ftype re = a[i], im = 0;
if(i + n < na) im = a[i + n];
A.set(i, fft::point(re, im));
}
for(size_t i = 0; i < std::min(n, nb); i++) {
fft::ftype re = bv[i], im = 0;
if(i + n < nb) im = bv[i + n];
B.set(i, fft::point(re, im));
}
A.fft();
B.fft();
A.dot(B);
A.ifft();
a.assign(2 * n, T(0));
for(size_t i = 0; i < n; i++) {
auto v = A.template get<fft::point>(i);
a[i] = v.real();
a[i + n] = v.imag();
}
a.resize(need);
} else {
// Generic fallback: use simple O(n^2) convolution from fft utilities.
fft::mul_slow(a, bv, need);
}
}
} // namespace cp_algo::math
#ifndef CP_ALGO_MATH_CONVOLUTION_HPP
#define CP_ALGO_MATH_CONVOLUTION_HPP
#include "fft.hpp"
#include "cvector.hpp"
#include <vector>
#include <algorithm>
#include <bit>
#include <type_traits>
#include <ranges>
namespace cp_algo::math{template<class VecA,class VecB>void convolution_prefix(VecA&a,VecB const&b,size_t need){using T=typename std::decay_t<VecA>::value_type;size_t na=std::min(need,std::size(a));size_t nb=std::min(need,std::size(b));a.resize(na);auto bv=b|std::views::take(nb);if(na==0||nb==0){a.clear();return;}if constexpr(modint_type<T>){fft::mul_truncate(a,bv,need);}else if constexpr(std::is_same_v<T,fft::point>){size_t conv_len=na+nb-1;size_t n=std::bit_ceil(conv_len);n=std::max(n,(size_t)fft::flen);fft::cvector A(n),B(n);for(size_t i=0;i<na;i++){A.set(i,a[i]);}for(size_t i=0;i<nb;i++){B.set(i,bv[i]);}A.fft();B.fft();A.dot(B);A.ifft();a.assign(need,T(0));for(size_t i=0;i<std::min(need,conv_len);i++){a[i]=A.template get<fft::point>(i);}}else if constexpr(std::is_same_v<T,fft::ftype>){size_t conv_len=na+nb-1;size_t n=std::bit_ceil(conv_len)/2;n=std::max(n,(size_t)fft::flen);fft::cvector A(n),B(n);for(size_t i=0;i<std::min(n,na);i++){fft::ftype re=a[i],im=0;if(i+n<na)im=a[i+n];A.set(i,fft::point(re,im));}for(size_t i=0;i<std::min(n,nb);i++){fft::ftype re=bv[i],im=0;if(i+n<nb)im=bv[i+n];B.set(i,fft::point(re,im));}A.fft();B.fft();A.dot(B);A.ifft();a.assign(2*n,T(0));for(size_t i=0;i<n;i++){auto v=A.template get<fft::point>(i);a[i]=v.real();a[i+n]=v.imag();}a.resize(need);}else{fft::mul_slow(a,bv,need);}}}
#endif
#line 1 "cp-algo/math/convolution.hpp"
#line 1 "cp-algo/math/fft.hpp"
#line 1 "cp-algo/number_theory/modint.hpp"
#line 1 "cp-algo/math/common.hpp"
#include <functional>
#include <cstdint>
#include <cassert>
namespace cp_algo::math{
#ifdef CP_ALGO_MAXN
const int maxn=CP_ALGO_MAXN;
#else
const int maxn=1<<19;
#endif
const int magic=64;auto bpow(auto const&x,auto n,auto const&one,auto op){if(n==0){return one;}else{auto t=bpow(x,n/2,one,op);t=op(t,t);if(n%2){t=op(t,x);}return t;}}auto bpow(auto x,auto n,auto ans){return bpow(x,n,ans,std::multiplies{});}template<typename T>T bpow(T const&x,auto n){return bpow(x,n,T(1));}inline constexpr auto inv2(auto x){assert(x%2);std::make_unsigned_t<decltype(x)>y=1;while(y*x!=1){y*=2-x*y;}return y;}}
#line 4 "cp-algo/number_theory/modint.hpp"
#include <iostream>
#line 6 "cp-algo/number_theory/modint.hpp"
namespace cp_algo::math{template<typename modint,typename _Int>struct modint_base{using Int=_Int;using UInt=std::make_unsigned_t<Int>;static constexpr size_t bits=sizeof(Int)*8;using Int2=std::conditional_t<bits<=32,int64_t,__int128_t>;using UInt2=std::conditional_t<bits<=32,uint64_t,__uint128_t>;constexpr static Int mod(){return modint::mod();}constexpr static Int remod(){return modint::remod();}constexpr static UInt2 modmod(){return UInt2(mod())*mod();}constexpr modint_base()=default;constexpr modint_base(Int2 rr){to_modint().setr(UInt((rr+modmod())%mod()));}modint inv()const{return bpow(to_modint(),mod()-2);}modint operator-()const{modint neg;neg.r=std::min(-r,remod()-r);return neg;}modint&operator/=(const modint&t){return to_modint()*=t.inv();}modint&operator*=(const modint&t){r=UInt(UInt2(r)*t.r%mod());return to_modint();}modint&operator+=(const modint&t){r+=t.r;r=std::min(r,r-remod());return to_modint();}modint&operator-=(const modint&t){r-=t.r;r=std::min(r,r+remod());return to_modint();}modint operator+(const modint&t)const{return modint(to_modint())+=t;}modint operator-(const modint&t)const{return modint(to_modint())-=t;}modint operator*(const modint&t)const{return modint(to_modint())*=t;}modint operator/(const modint&t)const{return modint(to_modint())/=t;}auto operator==(const modint&t)const{return to_modint().getr()==t.getr();}auto operator!=(const modint&t)const{return to_modint().getr()!=t.getr();}auto operator<=(const modint&t)const{return to_modint().getr()<=t.getr();}auto operator>=(const modint&t)const{return to_modint().getr()>=t.getr();}auto operator<(const modint&t)const{return to_modint().getr()<t.getr();}auto operator>(const modint&t)const{return to_modint().getr()>t.getr();}Int rem()const{UInt R=to_modint().getr();return R-(R>(UInt)mod()/2)*mod();}constexpr void setr(UInt rr){r=rr;}constexpr UInt getr()const{return r;}static UInt modmod8(){return UInt(8*modmod());}void add_unsafe(UInt t){r+=t;}void pseudonormalize(){r=std::min(r,r-modmod8());}modint const&normalize(){if(r>=(UInt)mod()){r%=mod();}return to_modint();}void setr_direct(UInt rr){r=rr;}UInt getr_direct()const{return r;}protected:UInt r;private:constexpr modint&to_modint(){return static_cast<modint&>(*this);}constexpr modint const&to_modint()const{return static_cast<modint const&>(*this);}};template<typename modint>concept modint_type=std::is_base_of_v<modint_base<modint,typename modint::Int>,modint>;template<modint_type modint>decltype(std::cin)&operator>>(decltype(std::cin)&in,modint&x){typename modint::UInt r;auto&res=in>>r;x.setr(r);return res;}template<modint_type modint>decltype(std::cout)&operator<<(decltype(std::cout)&out,modint const&x){return out<<x.getr();}template<auto m>struct modint:modint_base<modint<m>,decltype(m)>{using Base=modint_base<modint<m>,decltype(m)>;using Base::Base;static constexpr Base::Int mod(){return m;}static constexpr Base::UInt remod(){return m;}auto getr()const{return Base::r;}};template<typename Int=int>struct dynamic_modint:modint_base<dynamic_modint<Int>,Int>{using Base=modint_base<dynamic_modint<Int>,Int>;using Base::Base;static Base::UInt m_reduce(Base::UInt2 ab){if(mod()%2==0)[[unlikely]]{return typename Base::UInt(ab%mod());}else{typename Base::UInt2 m=typename Base::UInt(ab)*imod();return typename Base::UInt((ab+m*mod())>>Base::bits);}}static Base::UInt m_transform(Base::UInt a){if(mod()%2==0)[[unlikely]]{return a;}else{return m_reduce(a*pw128());}}dynamic_modint&operator*=(const dynamic_modint&t){Base::r=m_reduce(typename Base::UInt2(Base::r)*t.r);return*this;}void setr(Base::UInt rr){Base::r=m_transform(rr);}Base::UInt getr()const{typename Base::UInt res=m_reduce(Base::r);return std::min(res,res-mod());}static Int mod(){return m;}static Int remod(){return 2*m;}static Base::UInt imod(){return im;}static Base::UInt2 pw128(){return r2;}static void switch_mod(Int nm){m=nm;im=m%2?inv2(-m):0;r2=static_cast<Base::UInt>(static_cast<Base::UInt2>(-1)%m+1);}auto static with_mod(Int tmp,auto callback){struct scoped{Int prev=mod();~scoped(){switch_mod(prev);}}_;switch_mod(tmp);return callback();}private:static thread_local Int m;static thread_local Base::UInt im,r2;};template<typename Int>Int thread_local dynamic_modint<Int>::m=1;template<typename Int>dynamic_modint<Int>::Base::UInt thread_local dynamic_modint<Int>::im=-1;template<typename Int>dynamic_modint<Int>::Base::UInt thread_local dynamic_modint<Int>::r2=0;}
#line 1 "cp-algo/util/checkpoint.hpp"
#line 1 "cp-algo/util/big_alloc.hpp"
#include <map>
#include <deque>
#include <vector>
#include <string>
#include <cstddef>
#line 10 "cp-algo/util/big_alloc.hpp"
#if defined(__linux__) || defined(__unix__) || (defined(__APPLE__) && defined(__MACH__))
# define CP_ALGO_USE_MMAP 1
# include <sys/mman.h>
#else
# define CP_ALGO_USE_MMAP 0
#endif
namespace cp_algo{template<typename T,std::size_t Align=32>class big_alloc{static_assert(Align>=alignof(void*),"Align must be at least pointer-size");static_assert(std::popcount(Align)==1,"Align must be a power of two");public:using value_type=T;template<class U>struct rebind{using other=big_alloc<U,Align>;};constexpr bool operator==(const big_alloc&)const=default;constexpr bool operator!=(const big_alloc&)const=default;big_alloc()noexcept=default;template<typename U,std::size_t A>big_alloc(const big_alloc<U,A>&)noexcept{}[[nodiscard]]T*allocate(std::size_t n){std::size_t padded=round_up(n*sizeof(T));std::size_t align=std::max<std::size_t>(alignof(T),Align);
#if CP_ALGO_USE_MMAP
if(padded>=MEGABYTE){void*raw=mmap(nullptr,padded,PROT_READ|PROT_WRITE,MAP_PRIVATE|MAP_ANONYMOUS,-1,0);madvise(raw,padded,MADV_HUGEPAGE);madvise(raw,padded,MADV_POPULATE_WRITE);return static_cast<T*>(raw);}
#endif
return static_cast<T*>(::operator new(padded,std::align_val_t(align)));}void deallocate(T*p,std::size_t n)noexcept{if(!p)return;std::size_t padded=round_up(n*sizeof(T));std::size_t align=std::max<std::size_t>(alignof(T),Align);
#if CP_ALGO_USE_MMAP
if(padded>=MEGABYTE){munmap(p,padded);return;}
#endif
::operator delete(p,padded,std::align_val_t(align));}private:static constexpr std::size_t MEGABYTE=1<<20;static constexpr std::size_t round_up(std::size_t x)noexcept{return(x+Align-1)/Align*Align;}};template<typename T>using big_vector=std::vector<T,big_alloc<T>>;template<typename T>using big_basic_string=std::basic_string<T,std::char_traits<T>,big_alloc<T>>;template<typename T>using big_deque=std::deque<T,big_alloc<T>>;template<typename Key,typename Value,typename Compare=std::less<Key>>using big_map=std::map<Key,Value,Compare,big_alloc<std::pair<const Key,Value>>>;using big_string=big_basic_string<char>;}
#line 5 "cp-algo/util/checkpoint.hpp"
#include <chrono>
#line 8 "cp-algo/util/checkpoint.hpp"
namespace cp_algo{
#ifdef CP_ALGO_CHECKPOINT
big_map<big_string,double>checkpoints;double last;
#endif
template<bool final=false>void checkpoint([[maybe_unused]]auto const&_msg){
#ifdef CP_ALGO_CHECKPOINT
big_string msg=_msg;double now=(double)clock()/CLOCKS_PER_SEC;double delta=now-last;last=now;if(msg.size()&&!final){checkpoints[msg]+=delta;}if(final){for(auto const&[key,value]:checkpoints){std::cerr<<key<<": "<<value*1000<<" ms\n";}std::cerr<<"Total: "<<now*1000<<" ms\n";}
#endif
}template<bool final=false>void checkpoint(){checkpoint<final>("");}}
#line 1 "cp-algo/random/rng.hpp"
#line 4 "cp-algo/random/rng.hpp"
#include <random>
namespace cp_algo::random{std::mt19937_64 gen(std::chrono::steady_clock::now().time_since_epoch().count());uint64_t rng(){return gen();}}
#line 1 "cp-algo/math/cvector.hpp"
#line 1 "cp-algo/util/simd.hpp"
#include <experimental/simd>
#line 6 "cp-algo/util/simd.hpp"
#include <memory>
#if defined(__x86_64__) && !defined(CP_ALGO_DISABLE_AVX2)
#define CP_ALGO_SIMD_AVX2_TARGET _Pragma("GCC target(\"avx2\")")
#else
#define CP_ALGO_SIMD_AVX2_TARGET
#endif
#define CP_ALGO_SIMD_PRAGMA_PUSH \
_Pragma("GCC push_options")\_Pragma("GCC optimize(\"O3,unroll-loops\")")\CP_ALGO_SIMD_AVX2_TARGETCP_ALGO_SIMD_PRAGMA_PUSHnamespace cp_algo{template<typename T,size_t len>using simd[[gnu::vector_size(len*sizeof(T))]]=T;using i64x4=simd<int64_t,4>;using u64x4=simd<uint64_t,4>;using u32x8=simd<uint32_t,8>;using i32x4=simd<int32_t,4>;using u32x4=simd<uint32_t,4>;using i16x4=simd<int16_t,4>;using u8x32=simd<uint8_t,32>;using dx4=simd<double,4>;dx4 abs(dx4 a){return dx4{std::abs(a[0]),std::abs(a[1]),std::abs(a[2]),std::abs(a[3])};}static constexpr dx4 magic=dx4()+(3ULL<<51);inline i64x4 lround(dx4 x){return i64x4(x+magic)-i64x4(magic);}inline dx4 to_double(i64x4 x){return dx4(x+i64x4(magic))-magic;}inline dx4 round(dx4 a){return dx4{std::nearbyint(a[0]),std::nearbyint(a[1]),std::nearbyint(a[2]),std::nearbyint(a[3])};}inline u64x4 low32(u64x4 x){return x&uint32_t(-1);}inline auto swap_bytes(auto x){return decltype(x)(__builtin_shufflevector(u32x8(x),u32x8(x),1,0,3,2,5,4,7,6));}inline u64x4 montgomery_reduce(u64x4 x,uint32_t mod,uint32_t imod){
#ifdef __AVX2__
auto x_ninv=u64x4(_mm256_mul_epu32(__m256i(x),__m256i()+imod));x+=u64x4(_mm256_mul_epu32(__m256i(x_ninv),__m256i()+mod));
#else
auto x_ninv=u64x4(u32x8(low32(x))*imod);x+=x_ninv*uint64_t(mod);
#endif
return swap_bytes(x);}inline u64x4 montgomery_mul(u64x4 x,u64x4 y,uint32_t mod,uint32_t imod){
#ifdef __AVX2__
return montgomery_reduce(u64x4(_mm256_mul_epu32(__m256i(x),__m256i(y))),mod,imod);
#else
return montgomery_reduce(x*y,mod,imod);
#endif
}inline u32x8 montgomery_mul(u32x8 x,u32x8 y,uint32_t mod,uint32_t imod){return u32x8(montgomery_mul(u64x4(x),u64x4(y),mod,imod))|u32x8(swap_bytes(montgomery_mul(u64x4(swap_bytes(x)),u64x4(swap_bytes(y)),mod,imod)));}inline dx4 rotate_right(dx4 x){static constexpr u64x4 shuffler={3,0,1,2};return __builtin_shuffle(x,shuffler);}template<std::size_t Align=32>inline bool is_aligned(const auto*p)noexcept{return(reinterpret_cast<std::uintptr_t>(p)%Align)==0;}template<class Target>inline Target&vector_cast(auto&&p){return*reinterpret_cast<Target*>(std::assume_aligned<alignof(Target)>(&p));}}
#pragma GCC pop_options
#line 1 "cp-algo/util/complex.hpp"
#line 4 "cp-algo/util/complex.hpp"
#include <cmath>
#include <type_traits>
#line 7 "cp-algo/util/complex.hpp"
CP_ALGO_SIMD_PRAGMA_PUSHnamespace cp_algo{template<typename T>struct complex{using value_type=T;T x,y;inline constexpr complex():x(),y(){}inline constexpr complex(T const&x):x(x),y(){}inline constexpr complex(T const&x,T const&y):x(x),y(y){}inline complex&operator*=(T const&t){x*=t;y*=t;return*this;}inline complex&operator/=(T const&t){x/=t;y/=t;return*this;}inline complex operator*(T const&t)const{return complex(*this)*=t;}inline complex operator/(T const&t)const{return complex(*this)/=t;}inline complex&operator+=(complex const&t){x+=t.x;y+=t.y;return*this;}inline complex&operator-=(complex const&t){x-=t.x;y-=t.y;return*this;}inline complex operator*(complex const&t)const{return{x*t.x-y*t.y,x*t.y+y*t.x};}inline complex operator/(complex const&t)const{return*this*t.conj()/t.norm();}inline complex operator+(complex const&t)const{return complex(*this)+=t;}inline complex operator-(complex const&t)const{return complex(*this)-=t;}inline complex&operator*=(complex const&t){return*this=*this*t;}inline complex&operator/=(complex const&t){return*this=*this/t;}inline complex operator-()const{return{-x,-y};}inline complex conj()const{return{x,-y};}inline T norm()const{return x*x+y*y;}inline T abs()const{return std::sqrt(norm());}inline T const real()const{return x;}inline T const imag()const{return y;}inline T&real(){return x;}inline T&imag(){return y;}inline static constexpr complex polar(T r,T theta){return{T(r*cos(theta)),T(r*sin(theta))};}inline auto operator<=>(complex const&t)const=default;};template<typename T>inline complex<T>conj(complex<T>const&x){return x.conj();}template<typename T>inline T norm(complex<T>const&x){return x.norm();}template<typename T>inline T abs(complex<T>const&x){return x.abs();}template<typename T>inline T&real(complex<T>&x){return x.real();}template<typename T>inline T&imag(complex<T>&x){return x.imag();}template<typename T>inline T const real(complex<T>const&x){return x.real();}template<typename T>inline T const imag(complex<T>const&x){return x.imag();}template<typename T>inline constexpr complex<T>polar(T r,T theta){return complex<T>::polar(r,theta);}template<typename T>inline std::ostream&operator<<(std::ostream&out,complex<T>const&x){return out<<x.real()<<' '<<x.imag();}}
#pragma GCC pop_options
#line 7 "cp-algo/math/cvector.hpp"
#include <ranges>
#include <bit>
CP_ALGO_SIMD_PRAGMA_PUSHnamespace stdx=std::experimental;namespace cp_algo::math::fft{static constexpr size_t flen=4;using ftype=double;using vftype=dx4;using point=complex<ftype>;using vpoint=complex<vftype>;static constexpr vftype vz={};vpoint vi(vpoint const&r){return{-imag(r),real(r)};}struct cvector{big_vector<vpoint>r;cvector(size_t n){n=std::max(flen,std::bit_ceil(n));r.resize(n/flen);checkpoint("cvector create");}vpoint&at(size_t k){return r[k/flen];}vpoint at(size_t k)const{return r[k/flen];}template<class pt=point>inline void set(size_t k,pt const&t){if constexpr(std::is_same_v<pt,point>){real(r[k/flen])[k%flen]=real(t);imag(r[k/flen])[k%flen]=imag(t);}else{at(k)=t;}}template<class pt=point>inline pt get(size_t k)const{if constexpr(std::is_same_v<pt,point>){return{real(r[k/flen])[k%flen],imag(r[k/flen])[k%flen]};}else{return at(k);}}size_t size()const{return flen*r.size();}static constexpr size_t eval_arg(size_t n){if(n<pre_evals){return eval_args[n];}else{return eval_arg(n/2)|(n&1)<<(std::bit_width(n)-1);}}static constexpr point eval_point(size_t n){if(n%2){return-eval_point(n-1);}else if(n%4){return eval_point(n-2)*point(0,1);}else if(n/4<pre_evals){return evalp[n/4];}else{return polar<ftype>(1.,std::numbers::pi/(ftype)std::bit_floor(n)*(ftype)eval_arg(n));}}static constexpr std::array<point,32>roots=[](){std::array<point,32>res;for(size_t i=2;i<32;i++){res[i]=polar<ftype>(1.,std::numbers::pi/(1ull<<(i-2)));}return res;}();static constexpr point root(size_t n){return roots[std::bit_width(n)];}template<int step>static void exec_on_eval(size_t n,size_t k,auto&&callback){callback(k,root(4*step*n)*eval_point(step*k));}template<int step>static void exec_on_evals(size_t n,auto&&callback){point factor=root(4*step*n);for(size_t i=0;i<n;i++){callback(i,factor*eval_point(step*i));}}static void do_dot_iter(point rt,vpoint&Bv,vpoint const&Av,vpoint&res){res+=Av*Bv;real(Bv)=rotate_right(real(Bv));imag(Bv)=rotate_right(imag(Bv));auto x=real(Bv)[0],y=imag(Bv)[0];real(Bv)[0]=x*real(rt)-y*imag(rt);imag(Bv)[0]=x*imag(rt)+y*real(rt);}void dot(cvector const&t){size_t n=this->size();exec_on_evals<1>(n/flen,[&](size_t k,point rt)__attribute__((always_inline)){k*=flen;auto[Ax,Ay]=at(k);auto Bv=t.at(k);vpoint res=vz;for(size_t i=0;i<flen;i++){vpoint Av=vpoint(vz+Ax[i],vz+Ay[i]);do_dot_iter(rt,Bv,Av,res);}set(k,res);});checkpoint("dot");}template<bool partial=true>void ifft(){size_t n=size();if constexpr(!partial){point pi(0,1);exec_on_evals<4>(n/4,[&](size_t k,point rt)__attribute__((always_inline)){k*=4;point v1=conj(rt);point v2=v1*v1;point v3=v1*v2;auto A=get(k);auto B=get(k+1);auto C=get(k+2);auto D=get(k+3);set(k,(A+B)+(C+D));set(k+2,((A+B)-(C+D))*v2);set(k+1,((A-B)-pi*(C-D))*v1);set(k+3,((A-B)+pi*(C-D))*v3);});}bool parity=std::countr_zero(n)%2;if(parity){exec_on_evals<2>(n/(2*flen),[&](size_t k,point rt)__attribute__((always_inline)){k*=2*flen;vpoint cvrt={vz+real(rt),vz-imag(rt)};auto B=at(k)-at(k+flen);at(k)+=at(k+flen);at(k+flen)=B*cvrt;});}for(size_t leaf=3*flen;leaf<n;leaf+=4*flen){size_t level=std::countr_one(leaf+3);for(size_t lvl=4+parity;lvl<=level;lvl+=2){size_t i=(1<<lvl)/4;exec_on_eval<4>(n>>lvl,leaf>>lvl,[&](size_t k,point rt)__attribute__((always_inline)){k<<=lvl;vpoint v1={vz+real(rt),vz-imag(rt)};vpoint v2=v1*v1;vpoint v3=v1*v2;for(size_t j=k;j<k+i;j+=flen){auto A=at(j);auto B=at(j+i);auto C=at(j+2*i);auto D=at(j+3*i);at(j)=((A+B)+(C+D));at(j+2*i)=((A+B)-(C+D))*v2;at(j+i)=((A-B)-vi(C-D))*v1;at(j+3*i)=((A-B)+vi(C-D))*v3;}});}}checkpoint("ifft");for(size_t k=0;k<n;k+=flen){if constexpr(partial){set(k,get<vpoint>(k)/=vz+ftype(n/flen));}else{set(k,get<vpoint>(k)/=vz+ftype(n));}}}template<bool partial=true>void fft(){size_t n=size();bool parity=std::countr_zero(n)%2;for(size_t leaf=0;leaf<n;leaf+=4*flen){size_t level=std::countr_zero(n+leaf);level-=level%2!=parity;for(size_t lvl=level;lvl>=4;lvl-=2){size_t i=(1<<lvl)/4;exec_on_eval<4>(n>>lvl,leaf>>lvl,[&](size_t k,point rt)__attribute__((always_inline)){k<<=lvl;vpoint v1={vz+real(rt),vz+imag(rt)};vpoint v2=v1*v1;vpoint v3=v1*v2;for(size_t j=k;j<k+i;j+=flen){auto A=at(j);auto B=at(j+i)*v1;auto C=at(j+2*i)*v2;auto D=at(j+3*i)*v3;at(j)=(A+C)+(B+D);at(j+i)=(A+C)-(B+D);at(j+2*i)=(A-C)+vi(B-D);at(j+3*i)=(A-C)-vi(B-D);}});}}if(parity){exec_on_evals<2>(n/(2*flen),[&](size_t k,point rt)__attribute__((always_inline)){k*=2*flen;vpoint vrt={vz+real(rt),vz+imag(rt)};auto t=at(k+flen)*vrt;at(k+flen)=at(k)-t;at(k)+=t;});}if constexpr(!partial){point pi(0,1);exec_on_evals<4>(n/4,[&](size_t k,point rt)__attribute__((always_inline)){k*=4;point v1=rt;point v2=v1*v1;point v3=v1*v2;auto A=get(k);auto B=get(k+1)*v1;auto C=get(k+2)*v2;auto D=get(k+3)*v3;set(k,(A+C)+(B+D));set(k+1,(A+C)-(B+D));set(k+2,(A-C)+pi*(B-D));set(k+3,(A-C)-pi*(B-D));});}checkpoint("fft");}static constexpr size_t pre_evals=1<<16;static const std::array<size_t,pre_evals>eval_args;static const std::array<point,pre_evals>evalp;};const std::array<size_t,cvector::pre_evals>cvector::eval_args=[](){std::array<size_t,pre_evals>res={};for(size_t i=1;i<pre_evals;i++){res[i]=res[i>>1]|(i&1)<<(std::bit_width(i)-1);}return res;}();const std::array<point,cvector::pre_evals>cvector::evalp=[](){std::array<point,pre_evals>res={};res[0]=1;for(size_t n=1;n<pre_evals;n++){res[n]=polar<ftype>(1.,std::numbers::pi*ftype(eval_args[n])/ftype(4*std::bit_floor(n)));}return res;}();}
#pragma GCC pop_options
#line 9 "cp-algo/math/fft.hpp"
CP_ALGO_SIMD_PRAGMA_PUSHnamespace cp_algo::math::fft{template<modint_type base>struct dft{cvector A,B;static base factor,ifactor;using Int2=base::Int2;static bool _init;static int split(){static const int splt=int(std::sqrt(base::mod()))+1;return splt;}static uint32_t mod,imod;static void init(){if(!_init){factor=1+random::rng()%(base::mod()-1);ifactor=base(1)/factor;mod=base::mod();imod=-inv2<uint32_t>(base::mod());_init=true;}}static std::pair<vftype,vftype>do_split(auto const&a,size_t idx,u64x4 mul){if(idx>=std::size(a)){return std::pair{vftype(),vftype()};}u64x4 au={idx<std::size(a)?a[idx].getr():0,idx+1<std::size(a)?a[idx+1].getr():0,idx+2<std::size(a)?a[idx+2].getr():0,idx+3<std::size(a)?a[idx+3].getr():0};au=montgomery_mul(au,mul,mod,imod);au=au>=base::mod()?au-base::mod():au;auto ai=to_double(i64x4(au>=base::mod()/2?au-base::mod():au));auto quo=round(ai/split());return std::pair{ai-quo*split(),quo};}dft(size_t n):A(n),B(n){init();}dft(auto const&a,size_t n,bool partial=true):A(n),B(n){init();base b2x32=bpow(base(2),32);u64x4 cur={(bpow(factor,1)*b2x32).getr(),(bpow(factor,2)*b2x32).getr(),(bpow(factor,3)*b2x32).getr(),(bpow(factor,4)*b2x32).getr()};u64x4 step4=u64x4{}+(bpow(factor,4)*b2x32).getr();u64x4 stepn=u64x4{}+(bpow(factor,n)*b2x32).getr();for(size_t i=0;i<std::min(n,std::size(a));i+=flen){auto[rai,qai]=do_split(a,i,cur);auto[rani,qani]=do_split(a,n+i,montgomery_mul(cur,stepn,mod,imod));A.at(i)=vpoint(rai,rani);B.at(i)=vpoint(qai,qani);cur=montgomery_mul(cur,step4,mod,imod);}checkpoint("dft init");if(n){if(partial){A.fft();B.fft();}else{A.template fft<false>();B.template fft<false>();}}}static void do_dot_iter(point rt,vpoint&Cv,vpoint&Dv,vpoint const&Av,vpoint const&Bv,vpoint&AC,vpoint&AD,vpoint&BC,vpoint&BD){AC+=Av*Cv;AD+=Av*Dv;BC+=Bv*Cv;BD+=Bv*Dv;real(Cv)=rotate_right(real(Cv));imag(Cv)=rotate_right(imag(Cv));real(Dv)=rotate_right(real(Dv));imag(Dv)=rotate_right(imag(Dv));auto cx=real(Cv)[0],cy=imag(Cv)[0];auto dx=real(Dv)[0],dy=imag(Dv)[0];real(Cv)[0]=cx*real(rt)-cy*imag(rt);imag(Cv)[0]=cx*imag(rt)+cy*real(rt);real(Dv)[0]=dx*real(rt)-dy*imag(rt);imag(Dv)[0]=dx*imag(rt)+dy*real(rt);}template<bool overwrite=true,bool partial=true>void dot(auto const&C,auto const&D,auto&Aout,auto&Bout,auto&Cout)const{cvector::exec_on_evals<1>(A.size()/flen,[&](size_t k,point rt)__attribute__((always_inline)){k*=flen;vpoint AC,AD,BC,BD;AC=AD=BC=BD=vz;auto Cv=C.at(k),Dv=D.at(k);if constexpr(partial){auto[Ax,Ay]=A.at(k);auto[Bx,By]=B.at(k);for(size_t i=0;i<flen;i++){vpoint Av={vz+Ax[i],vz+Ay[i]},Bv={vz+Bx[i],vz+By[i]};do_dot_iter(rt,Cv,Dv,Av,Bv,AC,AD,BC,BD);}}else{AC=A.at(k)*Cv;AD=A.at(k)*Dv;BC=B.at(k)*Cv;BD=B.at(k)*Dv;}if constexpr(overwrite){Aout.at(k)=AC;Cout.at(k)=AD+BC;Bout.at(k)=BD;}else{Aout.at(k)+=AC;Cout.at(k)+=AD+BC;Bout.at(k)+=BD;}});checkpoint("dot");}void dot(auto&&C,auto const&D){dot(C,D,A,B,C);}static void do_recover_iter(size_t idx,auto A,auto B,auto C,auto mul,uint64_t splitsplit,auto&res){auto A0=lround(A),A1=lround(C),A2=lround(B);auto Ai=A0+A1*split()+A2*splitsplit+uint64_t(base::modmod());auto Au=montgomery_reduce(u64x4(Ai),mod,imod);Au=montgomery_mul(Au,mul,mod,imod);Au=Au>=base::mod()?Au-base::mod():Au;for(size_t j=0;j<flen;j++){res[idx+j].setr(typename base::UInt(Au[j]));}}void recover_mod(auto&&C,auto&res,size_t k){size_t check=(k+flen-1)/flen*flen;assert(res.size()>=check);size_t n=A.size();auto const splitsplit=base(split()*split()).getr();base b2x32=bpow(base(2),32);base b2x64=bpow(base(2),64);u64x4 cur={(bpow(ifactor,2)*b2x64).getr(),(bpow(ifactor,3)*b2x64).getr(),(bpow(ifactor,4)*b2x64).getr(),(bpow(ifactor,5)*b2x64).getr()};u64x4 step4=u64x4{}+(bpow(ifactor,4)*b2x32).getr();u64x4 stepn=u64x4{}+(bpow(ifactor,n)*b2x32).getr();for(size_t i=0;i<std::min(n,k);i+=flen){auto[Ax,Ay]=A.at(i);auto[Bx,By]=B.at(i);auto[Cx,Cy]=C.at(i);do_recover_iter(i,Ax,Bx,Cx,cur,splitsplit,res);if(i+n<k){do_recover_iter(i+n,Ay,By,Cy,montgomery_mul(cur,stepn,mod,imod),splitsplit,res);}cur=montgomery_mul(cur,step4,mod,imod);}checkpoint("recover mod");}void mul(auto&&C,auto const&D,auto&res,size_t k){assert(A.size()==C.size());size_t n=A.size();if(!n){res={};return;}dot(C,D);A.ifft();B.ifft();C.ifft();recover_mod(C,res,k);}void mul_inplace(auto&&B,auto&res,size_t k){mul(B.A,B.B,res,k);}void mul(auto const&B,auto&res,size_t k){mul(cvector(B.A),B.B,res,k);}big_vector<base>operator*=(dft&B){big_vector<base>res(2*A.size());mul_inplace(B,res,2*A.size());return res;}big_vector<base>operator*=(dft const&B){big_vector<base>res(2*A.size());mul(B,res,2*A.size());return res;}auto operator*(dft const&B)const{return dft(*this)*=B;}point operator[](int i)const{return A.get(i);}};template<modint_type base>base dft<base>::factor=1;template<modint_type base>base dft<base>::ifactor=1;template<modint_type base>bool dft<base>::_init=false;template<modint_type base>uint32_t dft<base>::mod={};template<modint_type base>uint32_t dft<base>::imod={};void mul_slow(auto&a,auto const&b,size_t k){if(std::empty(a)||std::empty(b)){a.clear();}else{size_t n=std::min(k,std::size(a));size_t m=std::min(k,std::size(b));a.resize(k);for(int j=int(k-1);j>=0;j--){a[j]*=b[0];for(int i=std::max(j-(int)n,0)+1;i<std::min(j+1,(int)m);i++){a[j]+=a[j-i]*b[i];}}}}size_t com_size(size_t as,size_t bs){if(!as||!bs){return 0;}return std::max(flen,std::bit_ceil(as+bs-1)/2);}void mul_truncate(auto&a,auto const&b,size_t k){using base=std::decay_t<decltype(a[0])>;if(std::min({k,std::size(a),std::size(b)})<magic){mul_slow(a,b,k);return;}auto n=std::max(flen,std::bit_ceil(std::min(k,std::size(a))+std::min(k,std::size(b))-1)/2);auto A=dft<base>(a|std::views::take(k),n);auto B=dft<base>(b|std::views::take(k),n);a.resize((k+flen-1)/flen*flen);A.mul_inplace(B,a,k);a.resize(k);}void mod_split(auto&&x,size_t n,auto k){using base=std::decay_t<decltype(k)>;dft<base>::init();assert(std::size(x)==2*n);u64x4 cur=u64x4{}+(k*bpow(base(2),32)).getr();for(size_t i=0;i<n;i+=flen){u64x4 xl={x[i].getr(),x[i+1].getr(),x[i+2].getr(),x[i+3].getr()};u64x4 xr={x[n+i].getr(),x[n+i+1].getr(),x[n+i+2].getr(),x[n+i+3].getr()};xr=montgomery_mul(xr,cur,dft<base>::mod,dft<base>::imod);xr=xr>=base::mod()?xr-base::mod():xr;auto t=xr;xr=xl-t;xl+=t;xl=xl>=base::mod()?xl-base::mod():xl;xr=xr>=base::mod()?xr+base::mod():xr;for(size_t k=0;k<flen;k++){x[i+k].setr(typename base::UInt(xl[k]));x[n+i+k].setr(typename base::UInt(xr[k]));}}cp_algo::checkpoint("mod split");}void cyclic_mul(auto&a,auto&&b,size_t k){assert(std::popcount(k)==1);assert(std::size(a)==std::size(b)&&std::size(a)==k);using base=std::decay_t<decltype(a[0])>;dft<base>::init();if(k<=(1<<16)){big_vector<base>ap(begin(a),end(a));mul_truncate(ap,b,2*k);mod_split(ap,k,bpow(dft<base>::factor,k));std::ranges::copy(ap|std::views::take(k),begin(a));return;}k/=2;auto factor=bpow(dft<base>::factor,k);mod_split(a,k,factor);mod_split(b,k,factor);auto la=std::span(a).first(k);auto lb=std::span(b).first(k);auto ra=std::span(a).last(k);auto rb=std::span(b).last(k);cyclic_mul(la,lb,k);auto A=dft<base>(ra,k/2);auto B=dft<base>(rb,k/2);A.mul_inplace(B,ra,k);base i2=base(2).inv();factor=factor.inv()*i2;for(size_t i=0;i<k;i++){auto t=(a[i]+a[i+k])*i2;a[i+k]=(a[i]-a[i+k])*factor;a[i]=t;}cp_algo::checkpoint("mod join");}auto make_copy(auto&&x){return x;}void cyclic_mul(auto&a,auto const&b,size_t k){return cyclic_mul(a,make_copy(b),k);}void mul(auto&a,auto&&b){size_t N=size(a)+size(b);if(N>(1<<20)){N--;size_t NN=std::bit_ceil(N);a.resize(NN);b.resize(NN);cyclic_mul(a,b,NN);a.resize(N);}else{mul_truncate(a,b,N-1);}}void mul(auto&a,auto const&b){size_t N=size(a)+size(b);if(N>(1<<20)){mul(a,make_copy(b));}else{mul_truncate(a,b,N-1);}}}
#pragma GCC pop_options
#line 6 "cp-algo/math/convolution.hpp"
#include <algorithm>
#line 10 "cp-algo/math/convolution.hpp"
namespace cp_algo::math{template<class VecA,class VecB>void convolution_prefix(VecA&a,VecB const&b,size_t need){using T=typename std::decay_t<VecA>::value_type;size_t na=std::min(need,std::size(a));size_t nb=std::min(need,std::size(b));a.resize(na);auto bv=b|std::views::take(nb);if(na==0||nb==0){a.clear();return;}if constexpr(modint_type<T>){fft::mul_truncate(a,bv,need);}else if constexpr(std::is_same_v<T,fft::point>){size_t conv_len=na+nb-1;size_t n=std::bit_ceil(conv_len);n=std::max(n,(size_t)fft::flen);fft::cvector A(n),B(n);for(size_t i=0;i<na;i++){A.set(i,a[i]);}for(size_t i=0;i<nb;i++){B.set(i,bv[i]);}A.fft();B.fft();A.dot(B);A.ifft();a.assign(need,T(0));for(size_t i=0;i<std::min(need,conv_len);i++){a[i]=A.template get<fft::point>(i);}}else if constexpr(std::is_same_v<T,fft::ftype>){size_t conv_len=na+nb-1;size_t n=std::bit_ceil(conv_len)/2;n=std::max(n,(size_t)fft::flen);fft::cvector A(n),B(n);for(size_t i=0;i<std::min(n,na);i++){fft::ftype re=a[i],im=0;if(i+n<na)im=a[i+n];A.set(i,fft::point(re,im));}for(size_t i=0;i<std::min(n,nb);i++){fft::ftype re=bv[i],im=0;if(i+n<nb)im=bv[i+n];B.set(i,fft::point(re,im));}A.fft();B.fft();A.dot(B);A.ifft();a.assign(2*n,T(0));for(size_t i=0;i<n;i++){auto v=A.template get<fft::point>(i);a[i]=v.real();a[i+n]=v.imag();}a.resize(need);}else{fft::mul_slow(a,bv,need);}}}