#include "bits/stdc++.h" #include using namespace std; #define rep(i,n) for(int (i)=0;(i)<(int)(n);++(i)) #define rer(i,l,u) for(int (i)=(int)(l);(i)<=(int)(u);++(i)) #define reu(i,l,u) for(int (i)=(int)(l);(i)<(int)(u);++(i)) static const int INF = 0x3f3f3f3f; static const long long INFL = 0x3f3f3f3f3f3f3f3fLL; typedef vector vi; typedef pair pii; typedef vector > vpii; typedef long long ll; template static void amin(T &x, U y) { if (y < x) x = y; } template static void amax(T &x, U y) { if (x < y) x = y; } #pragma GCC optimize ("O3") #pragma GCC target ("sse4") namespace uint_util { template struct Utils {}; template<> struct Utils { static void umul_full(uint32_t a, uint32_t b, uint32_t *lo, uint32_t *hi) { const uint64_t c = (uint64_t)a * b; *lo = (uint32_t)c; *hi = (uint32_t)(c >> 32); } static uint32_t umul_hi(uint32_t a, uint32_t b) { return (uint32_t)((uint64_t)a * b >> 32); } static uint32_t mulmod_invert(uint32_t b, uint32_t n) { return ((uint64_t)b << 32) / n; } static uint32_t umul_lo(uint32_t a, uint32_t b) { return a * b; } static uint32_t mulmod_precalculated(uint32_t a, uint32_t b, uint32_t n, uint32_t bninv) { const auto q = umul_hi(a, bninv); uint32_t r = a * b - q * n; if (r >= n) r -= n; return r; } static uint32_t invert_twoadic(uint32_t x) { uint32_t i = x, p; do { p = i * x; i *= 2 - p; } while (p != 1); return i; } }; } namespace modnum { template struct ModNumTypes { using Util = uint_util::Utils; template struct LazyModNum; //x < Lazy * P template struct LazyModNum { NumType x; LazyModNum() : x() {} template explicit LazyModNum(LazyModNum t) : x(t.x) { static_assert(L <= Lazy, "invalid conversion"); } static LazyModNum raw(NumType x) { LazyModNum r; r.x = x; return r; } template static LazyModNum *coerceArray(LazyModNum *a) { return reinterpret_cast(a); } bool operator==(LazyModNum that) const { static_assert(Lazy == 1, "cannot compare"); return x == that.x; } }; typedef LazyModNum<1> ModNum; class ModInfo { public: enum { MAX_ROOT_ORDER = 23 }; private: NumType P, P2; ModNum _one; NumType _twoadic_inverse; NumType _order; NumType _one_P_inv; //floor(W * (W rem P) / P) bool _support_fft; ModNum _roots[MAX_ROOT_ORDER + 1], _inv_roots[MAX_ROOT_ORDER + 1]; ModNum _inv_two_powers[MAX_ROOT_ORDER + 1]; public: NumType getP() const { return P; } NumType get_twoadic_inverse() const { return _twoadic_inverse; } ModNum one() const { return _one; } ModNum to_alt(NumType x) const { return ModNum::raw(Util::mulmod_precalculated(x, _one.x, P, _one_P_inv)); } NumType from_alt(ModNum x) const { return _reduce(x.x, 0); } bool support_fft() const { return _support_fft; } ModNum root(int n) const { assert(support_fft()); if (n > 0) { assert(n <= MAX_ROOT_ORDER); return _roots[n]; } else if (n < 0) { assert(n >= -MAX_ROOT_ORDER); return _inv_roots[-n]; } else { return one(); } } ModNum inv_two_power(int n) const { assert(support_fft()); assert(0 <= n && n <= MAX_ROOT_ORDER); return _inv_two_powers[n]; } ModNum add(ModNum a, ModNum b) const { auto c = a.x + b.x; if (c >= P) c -= P; return ModNum::raw(c); } ModNum sub(ModNum a, ModNum b) const { auto c = a.x + (P - b.x); if (c >= P) c -= P; return ModNum::raw(c); } LazyModNum<4> add_lazy(LazyModNum<2> a, LazyModNum<2> b) const { return LazyModNum<4>::raw(a.x + b.x); } LazyModNum<4> sub_lazy(LazyModNum<2> a, LazyModNum<2> b) const { return LazyModNum<4>::raw(a.x + (P2 - b.x)); } ModNum mul(ModNum a, ModNum b) const { NumType lo, hi; Util::umul_full(a.x, b.x, &lo, &hi); return ModNum::raw(_reduce(lo, hi)); } ModNum sqr(ModNum a) const { return mul(a, a); } template LazyModNum<2> mul_lazy(LazyModNum a, LazyModNum b) const { static_assert(LA + LB <= 5, "too lazy"); NumType lo, hi; Util::umul_full(a.x, b.x, &lo, &hi); return LazyModNum<2>::raw(_reduce_lazy(lo, hi)); } ModNum pow(ModNum a, NumType k) const { LazyModNum<2> base{ a }, res{ one() }; while (1) { if (k & 1) res = mul_lazy(res, base); if (k >>= 1) base = mul_lazy(base, base); else break; } return lazy_reduce_1(res); } ModNum inverse(ModNum a) const { return pow(a, _order - 1); } //a < 2P, res < P ModNum lazy_reduce_1(LazyModNum<2> a) const { NumType x = a.x; if (x >= P) x -= P; return ModNum::raw(x); } //a < 4P, res < 2P LazyModNum<2> lazy_reduce_2(LazyModNum<4> a) const { NumType x = a.x; if (x >= P2) x -= P2; return LazyModNum<2>::raw(x); } private: NumType _reduce(NumType lo, NumType hi) const { const auto q = Util::umul_lo(lo, _twoadic_inverse); const auto h = Util::umul_hi(q, P); NumType t = hi + P - h; if (t >= P) t -= P; return t; } NumType _reduce_lazy(NumType lo, NumType hi) const { const auto q = Util::umul_lo(lo, _twoadic_inverse); const auto h = Util::umul_hi(q, P); return hi + P - h; } public: static ModInfo make(NumType P, NumType order = NumType(-1)) { ModInfo res; res.P = P; res.P2 = P * 2; res._one.x = ~Util::umul_lo(Util::mulmod_invert(1, P), P) + 1; res._order = order == NumType(-1) ? P - 1 : order; res._twoadic_inverse = Util::invert_twoadic(P); res._one_P_inv = Util::mulmod_invert(res._one.x, P); res._support_fft = false; assert(res.mul(res.one(), res.one()) == res.one()); return res; } static ModInfo make_support_fft(NumType P, NumType order, NumType original_root, int valuation) { ModInfo res = make(P, order); _compute_fft_info(res, original_root, valuation); return res; } private: static void _compute_fft_info(ModInfo &res, NumType original_root, int valuation) { assert(res.P <= 1ULL << (sizeof(NumType) * 8 - 2)); assert(valuation >= MAX_ROOT_ORDER); res._support_fft = true; ModNum max_root = res.to_alt(original_root); for (int i = valuation; i > MAX_ROOT_ORDER; -- i) max_root = res.sqr(max_root); res._roots[MAX_ROOT_ORDER] = max_root; for (int i = MAX_ROOT_ORDER - 1; i >= 0; -- i) res._roots[i] = res.sqr(res._roots[i + 1]); res._inv_roots[MAX_ROOT_ORDER] = res.inverse(max_root); for (int i = MAX_ROOT_ORDER - 1; i >= 0; -- i) res._inv_roots[i] = res.sqr(res._inv_roots[i + 1]); res._inv_two_powers[0] = res.one(); res._inv_two_powers[1] = res.inverse(res.add(res.one(), res.one())); for (int i = 1; i < MAX_ROOT_ORDER; ++ i) res._inv_two_powers[i] = res.mul(res._inv_two_powers[1], res._inv_two_powers[i - 1]); assert(res.mul(res._roots[1], res._inv_roots[1]) == res.one()); assert(res.root(0) == res.one()); assert(!(res.root(1) == res.one())); } }; }; } namespace fft { using namespace modnum; using NumType = uint32_t; using ModNumType = ModNumTypes; template using LazyModNum = ModNumType::LazyModNum; using ModNum = ModNumType::ModNum; using ModInfo = ModNumType::ModInfo; using ModNumType32 = ModNumTypes; using ModNum32 = ModNumType32::ModNum; using ModInfo32 = ModNumType32::ModInfo; inline __m128i mod_lazy_reduce_2_sse2(const __m128i &a, const __m128i &p2, const __m128i &signbit) { const auto mask = _mm_cmpgt_epi32(_mm_xor_si128(p2, signbit), _mm_xor_si128(a, signbit)); const auto sub = _mm_andnot_si128(mask, p2); return _mm_sub_epi32(a, sub); } inline __m128i mod_reduce_lazy_sse2(const __m128i &a, const __m128i &p, const __m128i &twoadic_inverse) { const auto q = _mm_mul_epu32(a, twoadic_inverse); const auto h = _mm_shuffle_epi32(_mm_mul_epu32(q, p), _MM_SHUFFLE(3, 3, 1, 1)); return _mm_add_epi32(a, _mm_sub_epi32(p, h)); } inline __m128i mod_mul_lazy_sse2(const __m128i &a, const __m128i &b, const __m128i &p, const __m128i &twoadic_inverse) { const auto a02 = _mm_shuffle_epi32(a, _MM_SHUFFLE(2, 2, 0, 0)); const auto a13 = _mm_shuffle_epi32(a, _MM_SHUFFLE(3, 3, 1, 1)); const auto b02 = _mm_shuffle_epi32(b, _MM_SHUFFLE(2, 2, 0, 0)); const auto b13 = _mm_shuffle_epi32(b, _MM_SHUFFLE(3, 3, 1, 1)); const auto prod02 = _mm_mul_epu32(a02, b02); const auto prod13 = _mm_mul_epu32(a13, b13); const auto res02 = mod_reduce_lazy_sse2(prod02, p, twoadic_inverse); const auto res13 = mod_reduce_lazy_sse2(prod13, p, twoadic_inverse); const auto shuffled02 = _mm_shuffle_epi32(res02, _MM_SHUFFLE(0, 0, 3, 1)); const auto shuffled13 = _mm_shuffle_epi32(res13, _MM_SHUFFLE(0, 0, 3, 1)); return _mm_unpacklo_epi32(shuffled02, shuffled13); } inline __m128i mod_mul_sse2(const __m128i &a, const __m128i &b, const __m128i &p, const __m128i &twoadic_inverse) { __m128i t = mod_mul_lazy_sse2(a, b, p, twoadic_inverse); const auto mask = _mm_cmpgt_epi32(p, t); //signed compare const auto sub = _mm_andnot_si128(mask, p); return _mm_sub_epi32(t, sub); } inline __m128i mod_add_lazy_sse2(const __m128i &a, const __m128i &b) { return _mm_add_epi32(a, b); } inline __m128i mod_sub_lazy_sse2(const __m128i &a, const __m128i &b, const __m128i &p2) { return _mm_add_epi32(a, _mm_sub_epi32(p2, b)); } void ntt_dit_lazy_core_sse2(LazyModNum<2> *f_inout, int n, int sign, const ModInfo &mod) { LazyModNum<4> * const f = LazyModNum<4>::coerceArray(f_inout); int N = 1 << n; if (n <= 1) { if (n == 0) return; const auto a = f_inout[0]; const auto b = f_inout[1]; f_inout[0] = mod.lazy_reduce_2(mod.add_lazy(a, b)); f_inout[1] = mod.lazy_reduce_2(mod.sub_lazy(a, b)); return; } if (n & 1) { for (int i = 0; i < N; i += 2) { const auto a = f_inout[i + 0]; const auto b = f_inout[i + 1]; f[i + 0] = mod.add_lazy(a, b); f[i + 1] = mod.sub_lazy(a, b); } } if ((n & 1) == 0) { const auto imag = mod.root(2 * sign); for (int i = 0; i < N; i += 4) { const auto a0 = f_inout[i + 0]; const auto a2 = f_inout[i + 1]; const auto a1 = f_inout[i + 2]; const auto a3 = f_inout[i + 3]; const auto t02 = mod.lazy_reduce_2(mod.add_lazy(a0, a2)); const auto t13 = mod.lazy_reduce_2(mod.add_lazy(a1, a3)); f[i + 0] = mod.add_lazy(t02, t13); f[i + 2] = mod.sub_lazy(t02, t13); const auto u02 = mod.lazy_reduce_2(mod.sub_lazy(a0, a2)); const auto u13 = mod.mul_lazy(mod.sub_lazy(a1, a3), imag); f[i + 1] = mod.add_lazy(u02, u13); f[i + 3] = mod.sub_lazy(u02, u13); } } else { const auto imag = mod.root(2 * sign); const auto omega = mod.root(3 * sign); for (int i = 0; i < N; i += 8) { const auto a0 = mod.lazy_reduce_2(f[i + 0]); const auto a2 = mod.lazy_reduce_2(f[i + 2]); const auto a1 = mod.lazy_reduce_2(f[i + 4]); const auto a3 = mod.lazy_reduce_2(f[i + 6]); const auto t02 = mod.lazy_reduce_2(mod.add_lazy(a0, a2)); const auto t13 = mod.lazy_reduce_2(mod.add_lazy(a1, a3)); f[i + 0] = mod.add_lazy(t02, t13); f[i + 4] = mod.sub_lazy(t02, t13); const auto u02 = mod.lazy_reduce_2(mod.sub_lazy(a0, a2)); const auto u13 = mod.mul_lazy(mod.sub_lazy(a1, a3), imag); f[i + 2] = mod.add_lazy(u02, u13); f[i + 6] = mod.sub_lazy(u02, u13); } ModNum w = omega, w2 = imag, w3 = mod.mul(w2, w); for (int i = 1; i < N; i += 8) { const auto a0 = mod.lazy_reduce_2(f[i + 0]); const auto a2 = mod.mul_lazy(f[i + 2], w2); const auto a1 = mod.mul_lazy(f[i + 4], w); const auto a3 = mod.mul_lazy(f[i + 6], w3); const auto t02 = mod.lazy_reduce_2(mod.add_lazy(a0, a2)); const auto t13 = mod.lazy_reduce_2(mod.add_lazy(a1, a3)); f[i + 0] = mod.add_lazy(t02, t13); f[i + 4] = mod.sub_lazy(t02, t13); const auto u02 = mod.lazy_reduce_2(mod.sub_lazy(a0, a2)); const auto u13 = mod.mul_lazy(mod.sub_lazy(a1, a3), imag); f[i + 2] = mod.add_lazy(u02, u13); f[i + 6] = mod.sub_lazy(u02, u13); } } for (int m = 4 + (n & 1); m <= n; m += 2) { int M = 1 << m, M_4 = M >> 2; const auto o = mod.root(m * sign), o2 = mod.root((m - 1) * sign), o4 = mod.root((m - 2) * sign); const auto p = _mm_set1_epi32(mod.getP()); const auto p2 = _mm_set1_epi32(mod.getP() * 2); const auto twoadic_inverse = _mm_set1_epi32(mod.get_twoadic_inverse()); const auto imag = _mm_set1_epi32(mod.root(2 * sign).x); const auto omega = _mm_set1_epi32(o4.x); const auto signbit = _mm_set1_epi32((int)(1U << 31)); __m128i w = _mm_set_epi32(mod.mul(o, o2).x, o2.x, o.x, mod.one().x); for (int j = 0; j < M_4; j += 4) { const auto w2 = mod_mul_sse2(w, w, p, twoadic_inverse); const auto w3 = mod_mul_sse2(w2, w, p, twoadic_inverse); for (int i = j; i < N; i += M) { const auto f0 = _mm_loadu_si128(reinterpret_cast<__m128i*>(f + i + M_4 * 0)); const auto f1 = _mm_loadu_si128(reinterpret_cast<__m128i*>(f + i + M_4 * 1)); const auto f2 = _mm_loadu_si128(reinterpret_cast<__m128i*>(f + i + M_4 * 2)); const auto f3 = _mm_loadu_si128(reinterpret_cast<__m128i*>(f + i + M_4 * 3)); const auto a0 = mod_lazy_reduce_2_sse2(f0, p2, signbit); const auto a2 = mod_mul_lazy_sse2(f1, w2, p, twoadic_inverse); const auto a1 = mod_mul_lazy_sse2(f2, w, p, twoadic_inverse); const auto a3 = mod_mul_lazy_sse2(f3, w3, p, twoadic_inverse); const auto t02 = mod_lazy_reduce_2_sse2(mod_add_lazy_sse2(a0, a2), p2, signbit); const auto t13 = mod_lazy_reduce_2_sse2(mod_add_lazy_sse2(a1, a3), p2, signbit); const auto r0 = mod_add_lazy_sse2(t02, t13); const auto r2 = mod_sub_lazy_sse2(t02, t13, p2); const auto u02 = mod_lazy_reduce_2_sse2(mod_sub_lazy_sse2(a0, a2, p2), p2, signbit); const auto u13 = mod_mul_lazy_sse2(mod_sub_lazy_sse2(a1, a3, p2), imag, p, twoadic_inverse); const auto r1 = mod_add_lazy_sse2(u02, u13); const auto r3 = mod_sub_lazy_sse2(u02, u13, p2); _mm_storeu_si128(reinterpret_cast<__m128i*>(f + i + M_4 * 0), r0); _mm_storeu_si128(reinterpret_cast<__m128i*>(f + i + M_4 * 1), r1); _mm_storeu_si128(reinterpret_cast<__m128i*>(f + i + M_4 * 2), r2); _mm_storeu_si128(reinterpret_cast<__m128i*>(f + i + M_4 * 3), r3); } w = mod_mul_sse2(w, omega, p, twoadic_inverse); } } for (int i = 0; i < N; ++ i) f_inout[i] = mod.lazy_reduce_2(f[i]); } void ntt_dit_lazy_core(LazyModNum<2> *f_inout, int n, int sign, const ModInfo &mod) { ntt_dit_lazy_core_sse2(f_inout, n, sign, mod); } template void bit_reverse_permute(T *f, int n) { int N = 1 << n, N_2 = N >> 1, r = 0; for (int x = 1; x < N; ++ x) { int h = N_2; while (((r ^= h) & h) == 0) h >>= 1; if (r > x) swap(f[x], f[r]); } } void ntt_dit_lazy(LazyModNum<2> *f, int n, int sign, const ModInfo &mod) { bit_reverse_permute(f, n); ntt_dit_lazy_core(f, n, sign, mod); } template void componentwise_product_lazy(LazyModNum<2> *res, const LazyModNum *f, const LazyModNum *g, int N, const ModInfo &mod) { for (int i = 0; i < N; ++ i) res[i] = mod.mul_lazy(f[i], g[i]); } void normalize_and_lazy_reduce(LazyModNum<2> *f, int n, const ModInfo &mod) { const auto f_out = ModNum::coerceArray(f); int N = 1 << n; ModNum inv = mod.inv_two_power(n); assert(mod.mul(inv, mod.to_alt(N)) == mod.one()); for (int i = 0; i < N; ++ i) f_out[i] = mod.lazy_reduce_1(mod.mul_lazy(f[i], inv)); } void convolute(ModNum *f_in, ModNum *g_in, int n, const ModInfo &mod) { assert(mod.support_fft()); const auto f = LazyModNum<2>::coerceArray(f_in); const auto g = LazyModNum<2>::coerceArray(g_in); ntt_dit_lazy(f, n, +1, mod); ntt_dit_lazy(g, n, +1, mod); componentwise_product_lazy(f, f, g, 1 << n, mod); ntt_dit_lazy(f, n, -1, mod); normalize_and_lazy_reduce(f, n, mod); } void auto_convolute(ModNum *f_in, int n, const ModInfo &mod) { assert(mod.support_fft()); const auto f = LazyModNum<2>::coerceArray(f_in); ntt_dit_lazy(f, n, +1, mod); componentwise_product_lazy(f, f, f, 1 << n, mod); ntt_dit_lazy(f, n, -1, mod); normalize_and_lazy_reduce(f, n, mod); } enum { MULTIPRIME_NUM = 3 }; static const ModInfo fft_prime_mod0 = ModInfo::make_support_fft(998244353, -1, 31, 23); static const ModInfo fft_prime_mod1 = ModInfo::make_support_fft(897581057, -1, 45, 23); static const ModInfo fft_prime_mod2 = ModInfo::make_support_fft(880803841, -1, 211, 23); const ModInfo * const fft_prime_mods[MULTIPRIME_NUM] = { &fft_prime_mod0, &fft_prime_mod1, &fft_prime_mod2 }; void multiprime_compose(ModNum32 *res, const ModInfo32 &mod_res, const ModNum *f[MULTIPRIME_NUM], int N, const ModInfo * const mods[MULTIPRIME_NUM]) { const auto f0 = f[0], f1 = f[1], f2 = f[2]; const auto &mod0 = *mods[0], &mod1 = *mods[1], &mod2 = *mods[2]; const auto P0 = mod0.getP(), P1 = mod1.getP(), P2 = mod2.getP(); const auto P_res = mod_res.getP(); const auto t1 = mod1.inverse(mod1.to_alt(P0)); const auto t2 = mod2.inverse(mod2.to_alt((uint64_t)P0 * P1 % P2)); const auto p01 = mod_res.to_alt((uint64_t)P0 * P1 % P_res); for (int i = 0; i < N; ++ i) { const auto a0 = mod0.from_alt(f0[i]), a1 = mod1.from_alt(f1[i]), a2 = mod2.from_alt(f2[i]); const auto d1 = mod1.sub(mod1.to_alt(a1), mod1.to_alt(a0)); const auto h1 = mod1.from_alt(mod1.mul(d1, t1)); const auto a01 = a0 + (uint64_t)P0 * h1; const auto d2 = mod2.sub(mod2.to_alt(a2), mod2.to_alt(a01 % P2)); const auto h2 = mod2.from_alt(mod2.mul(d2, t2)); res[i] = mod_res.add(mod_res.to_alt(a01 % P_res), mod_res.mul(mod_res.to_alt(h2 % P_res), p01)); } } void multiprime_decompose(ModNum *res[MULTIPRIME_NUM], const ModNum32 *f, int N, const ModInfo32 &f_mod, const ModInfo * const mods[MULTIPRIME_NUM]) { for (int i = 0; i < N; ++ i) { const auto a = f_mod.from_alt(f[i]); for (int k = 0; k < MULTIPRIME_NUM; ++ k) res[k][i] = mods[k]->to_alt(a); } } void multiprime_convolute(ModNum32 *res, int resN, const ModNum32 *f, int fN, const ModNum32 *g, int gN, int n, const ModInfo32 &mod) { int N = 1 << n; assert(fN <= N && gN <= N && resN <= N); //implicit zero-fill unique_ptr workspace(new ModNum[N * MULTIPRIME_NUM * 2]); ModNum *fs[MULTIPRIME_NUM], *gs[MULTIPRIME_NUM]; for (int k = 0; k < MULTIPRIME_NUM; ++ k) { fs[k] = workspace.get() + (k * 2 + 0) * N; gs[k] = workspace.get() + (k * 2 + 1) * N; } multiprime_decompose(fs, f, fN, mod, fft_prime_mods); multiprime_decompose(gs, g, gN, mod, fft_prime_mods); for (int k = 0; k < MULTIPRIME_NUM; ++ k) convolute(fs[k], gs[k], n, *fft_prime_mods[k]); multiprime_compose(res, mod, const_cast(fs), resN, fft_prime_mods); } void multiprime_auto_convolute(ModNum32 *res, int resN, const ModNum32 *f, int fN, int n, const ModInfo32 &mod) { int N = 1 << n; assert(fN <= N && resN <= N); unique_ptr workspace(new ModNum[N * MULTIPRIME_NUM]); ModNum *fs[MULTIPRIME_NUM]; for (int k = 0; k < MULTIPRIME_NUM; ++ k) fs[k] = workspace.get() + k * N; multiprime_decompose(fs, f, fN, mod, fft_prime_mods); for (int k = 0; k < MULTIPRIME_NUM; ++ k) auto_convolute(fs[k], n, *fft_prime_mods[k]); multiprime_compose(res, mod, const_cast(fs), resN, fft_prime_mods); } } struct ModInt { using NumType = uint32_t; using ModNumType = modnum::ModNumTypes; using ModNum = ModNumType::ModNum; using ModInfo = ModNumType::ModInfo; public: ModNum x; ModInt() : x() {} ModInt(NumType num) : x(mod.to_alt(num)) {} ModInt(int num) : x(mod.to_alt(num >= 0 ? num : mod.getP() + num % (int)mod.getP())) {} NumType get() const { return mod.from_alt(x); } static ModInt raw(ModNum x) { ModInt r; r.x = x; return r; } static ModInt one() { return raw(mod.one()); } ModInt operator+(ModInt that) const { return raw(mod.add(x, that.x)); } ModInt &operator+=(ModInt that) { return *this = *this + that; } ModInt operator-(ModInt that) const { return raw(mod.sub(x, that.x)); } ModInt &operator-=(ModInt that) { return *this = *this - that; } ModInt operator-() const { return raw(mod.sub(ModNum(), x)); } ModInt operator*(ModInt that) const { return raw(mod.mul(x, that.x)); } ModInt &operator*=(ModInt that) { return *this = *this * that; } ModInt inverse() const { return raw(mod.inverse(x)); } ModInt operator/(ModInt that) const { return *this * that.inverse(); } ModInt &operator/=(ModInt that) { return *this = *this / that.inverse(); } bool operator==(ModInt that) const { return x == that.x; } bool operator!=(ModInt that) const { return !(*this == that); } private: static ModInfo mod; public: static const ModInfo &get_mod_info() { return mod; } static NumType getMod() { return mod.getP(); } static void set_mod(NumType P, NumType order = -1) { mod = ModInfo::make(P, order); } }; ModInt::ModInfo ModInt::mod; typedef ModInt mint; namespace mod_polynomial { struct Polynomial { typedef mint R; static R ZeroR() { return R(); } static R OneR() { return R::one(); } static bool IsZeroR(R r) { return r == ZeroR(); } struct NumberTable { std::vector natural_numbers; std::vector inverse_numbers; std::vector factorials; std::vector inverse_factorials; int size() const { return (int)natural_numbers.size(); } }; std::vector coeffs; Polynomial() {} explicit Polynomial(R c0) : coeffs(1, c0) {} explicit Polynomial(R c0, R c1) : coeffs(2) { coeffs[0] = c0, coeffs[1] = c1; } template Polynomial(It be, It en) : coeffs(be, en) {} static Polynomial Zero() { return Polynomial(); } static Polynomial One() { return Polynomial(OneR()); } static Polynomial X() { return Polynomial(ZeroR(), OneR()); } void resize(int n) { coeffs.resize(n); } void clear() { coeffs.clear(); } R *data() { return coeffs.empty() ? NULL : &coeffs[0]; } const R *data() const { return coeffs.empty() ? NULL : &coeffs[0]; } int size() const { return static_cast(coeffs.size()); } bool empty() const { return coeffs.empty(); } int degree() const { return size() - 1; } bool normalized() const { return coeffs.empty() || coeffs.back() != ZeroR(); } bool monic() const { return !coeffs.empty() && coeffs.back() == OneR(); } R get(int i) const { return 0 <= i && i < size() ? coeffs[i] : ZeroR(); } void set(int i, R x) { if (size() <= i) resize(i + 1); coeffs[i] = x; } void normalize() { while (!empty() && IsZeroR(coeffs.back())) coeffs.pop_back(); } R evaluate(R x) const { if (empty()) return R(); R r = coeffs.back(); for (int i = size() - 2; i >= 0; -- i) { r *= x; r += coeffs[i]; } return r; } Polynomial &operator+=(const Polynomial &that) { int m = size(), n = that.size(); if (m < n) resize(n); _add(data(), that.data(), n); return *this; } Polynomial operator+(const Polynomial &that) const { return Polynomial(*this) += that; } Polynomial &operator-=(const Polynomial &that) { int m = size(), n = that.size(); if (m < n) resize(n); _subtract(data(), that.data(), n); return *this; } Polynomial operator-(const Polynomial &that) const { return Polynomial(*this) -= that; } Polynomial &operator*=(R r) { _multiply_1(data(), size(), r); return *this; } Polynomial operator*(R r) const { Polynomial res; res.resize(size()); _multiply_1(res.data(), data(), size(), r); return res; } Polynomial operator*(const Polynomial &that) const { Polynomial r; multiply(r, *this, that); return r; } Polynomial &operator*=(const Polynomial &that) { multiply(*this, *this, that); return *this; } static void multiply(Polynomial &res, const Polynomial &p, const Polynomial &q) { int pn = p.size(), qn = q.size(); if (pn < qn) return multiply(res, q, p); if (&res == &p || &res == &q) { Polynomial tmp; multiply(tmp, p, q); res = tmp; return; } if (qn == 0) { res.coeffs.clear(); } else { res.resize(pn + qn - 1); _multiply_select_method(res.data(), p.data(), pn, q.data(), qn); } } Polynomial operator-() const { Polynomial res; res.resize(size()); _negate(res.data(), data(), size()); return res; } Polynomial precomputeRevInverse(int n) const { Polynomial res; res.resize(n); _precompute_reverse_inverse(res.data(), n, data(), size()); return res; } static void divideRemainderPrecomputedRevInverse(Polynomial ", Polynomial &rem, const Polynomial &p, const Polynomial &q, const Polynomial &inv) { assert(" != &p && " != &q && " != &inv); int pn = p.size(), qn = q.size(); assert(inv.size() >= pn - qn + 1); quot.resize(std::max(0, pn - qn + 1)); rem.resize(qn - 1); _divide_remainder_precomputed_inverse(quot.data(), rem.data(), p.data(), pn, q.data(), qn, inv.data()); quot.normalize(); rem.normalize(); } Polynomial computeRemainderPrecomputedRevInverse(const Polynomial &q, const Polynomial &inv) const { Polynomial quot, rem; divideRemainderPrecomputedRevInverse(quot, rem, *this, q, inv); return rem; } Polynomial powerMod(long long K, const Polynomial &q) const { int qn = q.size(); assert(K >= 0 && qn > 0); assert(q.monic()); if (qn == 1) return Polynomial(); if (K == 0) return One(); Polynomial inv = q.precomputeRevInverse(std::max(size() - qn + 1, qn)); Polynomial p = this->computeRemainderPrecomputedRevInverse(q, inv); int l = 0; while ((K >> l) > 1) ++ l; Polynomial res = p; for (-- l; l >= 0; -- l) { res *= res; res = res.computeRemainderPrecomputedRevInverse(q, inv); if (K >> l & 1) { res *= p; res = res.computeRemainderPrecomputedRevInverse(q, inv); } } return res; } Polynomial reverse(int n) { assert(size() <= n); Polynomial r; r.resize(n); for (int i = 0; i < n; ++ i) r.set(n - 1 - i, get(i)); return r; } static void clearNumberTable() { _numberTable = NumberTable(); } static const NumberTable &getNumberTable(int size) { extendNumberTable(size); return _numberTable; } static void extendNumberTable(int size) { int old_size = _numberTable.size(); if (old_size >= size) return; if (old_size * 2 > size) size = old_size * 2; NumberTable &nt = _numberTable; nt.natural_numbers.resize(size); nt.inverse_numbers.resize(size); nt.factorials.resize(size); nt.inverse_factorials.resize(size); if (old_size == 0) { nt.natural_numbers[0] = ZeroR(); nt.inverse_numbers[0] = ZeroR(); nt.factorials[0] = OneR(); nt.inverse_factorials[0] = OneR(); ++ old_size; } for (int n = old_size; n < size; ++ n) { nt.natural_numbers[n] = nt.natural_numbers[n - 1] + OneR(); if (IsZeroR(nt.natural_numbers[n])) { std::cerr << "No inverse of zero: " << n << std::endl; std::abort(); } nt.factorials[n] = nt.factorials[n - 1] * nt.natural_numbers[n]; } nt.inverse_factorials[size - 1] = nt.factorials[size - 1].inverse(); for (int n = size - 2; n >= old_size; -- n) nt.inverse_factorials[n] = nt.inverse_factorials[n + 1] * nt.natural_numbers[n + 1]; for (int n = old_size; n < size; ++ n) nt.inverse_numbers[n] = nt.inverse_factorials[n] * nt.factorials[n - 1]; } Polynomial derivative() const { if (empty()) return *this; Polynomial res; res.resize(size() - 1); _derivative(res.data(), data(), size(), getNumberTable(size()).natural_numbers.data()); return res; } Polynomial integrate() const { Polynomial res; res.resize(size() + 1); _integral(res.data(), data(), size(), getNumberTable(size() + 1).inverse_numbers.data()); return res; } Polynomial inverse(int n) const { Polynomial res; res.resize(n); _inverse_power_series(res.data(), n, data(), size()); return res; } Polynomial logarithm(int n) const { Polynomial res; res.resize(n); const NumberTable &nt = getNumberTable(std::max(size(), n)); _log_power_series(res.data(), n, data(), size(), nt.natural_numbers.data(), nt.inverse_numbers.data()); return res; } Polynomial exponential(int n) const { Polynomial res; res.resize(n); const NumberTable &nt = getNumberTable(std::max(size(), n)); _exp_power_series(res.data(), n, data(), size(), nt.natural_numbers.data(), nt.inverse_numbers.data()); return res; } static int MULTIPRIME_FFT_THRESHOLD; private: static NumberTable _numberTable; class WorkSpaceStack; static void _fill_zero(R *res, int n); static void _copy(R *res, const R *p, int n); static void _negate(R *res, const R *p, int n); static void _add(R *p, const R *q, int n); static void _add(R *res, const R *p, int pn, const R *q, int qn); static void _subtract(R *p, const R *q, int n); static void _subtract(R *res, const R *p, int pn, const R *q, int qn); static void _multiply_select_method(R *res, const R *p, int pn, const R *q, int qn); static void _square_select_method(R *res, const R *p, int pn); static void _multiply_1(R *p, const R *q, int n, R c0); static void _multiply_1(R *p, int n, R c0); static void _multiply_power_of_two(R *res, const R *p, int n, int k); static void _divide_power_of_two(R *res, const R *p, int n, int k); static void _schoolbook_multiplication(R *res, const R *p, int pn, const R *q, int qn); static void _multiprime_fft(R *res, const R *p, int pn, const R *q, int qn); static void _reverse(R *res, const R *p, int pn); static void _inverse_power_series(R *res, int resn, const R *p, int pn); static void _precompute_reverse_inverse(R *res, int resn, const R *p, int pn); static void _divide_precomputed_inverse(R *res, int resn, const R *revp, int pn, const R *inv); static void _divide_remainder_precomputed_inverse(R *quot, R *rem, const R *p, int pn, const R *q, int qn, const R *inv); static void _derivative(R *res, const R *p, int pn, const R *natural_numbers); static void _integral(R *res, const R *p, int pn, const R *inverse_numbers); static void _log_power_series(R *res, int resn, const R *p, int pn, const R *natural_numbers, const R *inverse_numbers); static void _exp_power_series(R *res, int resn, const R *p, int pn, const R *natural_numbers, const R *inverse_numbers); }; int Polynomial::MULTIPRIME_FFT_THRESHOLD = 8; Polynomial::NumberTable Polynomial::_numberTable; void Polynomial::_fill_zero(R *res, int n) { for (int i = 0; i < n; ++ i) res[i] = ZeroR(); } void Polynomial::_copy(R *res, const R *p, int n) { for (int i = 0; i < n; ++ i) res[i] = p[i]; } void Polynomial::_negate(R *res, const R *p, int n) { for (int i = 0; i < n; ++ i) res[i] = -p[i]; } void Polynomial::_add(R *res, const R *p, int pn, const R *q, int qn) { for (int i = 0; i < qn; ++ i) res[i] = p[i] + q[i]; _copy(res + qn, p + qn, pn - qn); } void Polynomial::_subtract(R *res, const R *p, int pn, const R *q, int qn) { for (int i = 0; i < qn; ++ i) res[i] = p[i] - q[i]; _copy(res + qn, p + qn, pn - qn); } void Polynomial::_add(R *p, const R *q, int n) { _add(p, p, n, q, n); } void Polynomial::_subtract(R *p, const R *q, int n) { _subtract(p, p, n, q, n); } void Polynomial::_multiply_1(R *res, const R *p, int n, R c0) { for (int i = 0; i < n; ++ i) res[i] = p[i] * c0; } void Polynomial::_multiply_1(R *p, int n, R c0) { _multiply_1(p, p, n, c0); } void Polynomial::_multiply_power_of_two(R *res, const R *p, int n, int k) { assert(0 < k && k < 31); R mul = R(1 << k); _multiply_1(res, p, n, mul); } void Polynomial::_divide_power_of_two(R *res, const R *p, int n, int k) { assert(0 < k && k < 31); static const R Inv2 = R(2).inverse(); R inv = k == 1 ? Inv2 : R(1 << k).inverse(); _multiply_1(res, p, n, inv); } void Polynomial::_multiply_select_method(R *res, const R *p, int pn, const R *q, int qn) { if (pn < qn) std::swap(p, q), std::swap(pn, qn); assert(res != p && res != q && pn >= qn && qn > 0); int rn = pn + qn - 1; if (qn == 1) { _multiply_1(res, p, pn, q[0]); } else if (qn < MULTIPRIME_FFT_THRESHOLD) { _schoolbook_multiplication(res, p, pn, q, qn); } else { _multiprime_fft(res, p, pn, q, qn); } } void Polynomial::_square_select_method(R *res, const R *p, int pn) { _multiply_select_method(res, p, pn, p, pn); } void Polynomial::_schoolbook_multiplication(R *res, const R *p, int pn, const R *q, int qn) { if (qn == 1) { _multiply_1(res, p, pn, q[0]); return; } assert(res != p && res != q && pn >= qn && qn > 0); _fill_zero(res, pn + qn - 1); for (int i = 0; i < pn; ++ i) for (int j = 0; j < qn; ++ j) res[i + j] += p[i] * q[j]; } void Polynomial::_multiprime_fft(R *res, const R *p, int pn, const R *q, int qn) { int resn = pn + qn - 1; int n = 0; while ((1 << n) < resn) ++ n; if (p == q) { assert(pn == qn); fft::multiprime_auto_convolute(reinterpret_cast(res), resn, reinterpret_cast(p), pn, n, mint::get_mod_info()); } else { fft::multiprime_convolute(reinterpret_cast(res), resn, reinterpret_cast(p), pn, reinterpret_cast(q), qn, n, mint::get_mod_info()); } } void Polynomial::_reverse(R *res, const R *p, int pn) { if (res == p) { std::reverse(res, res + pn); } else { for (int i = 0; i < pn; ++ i) res[pn - 1 - i] = p[i]; } } void Polynomial::_inverse_power_series(R *res, int resn, const R *p, int pn) { if (resn == 0) return; assert(res != p); assert(pn > 0); assert(!IsZeroR(p[0])); if (p[0] != OneR()) { unique_ptr tmpp(new R[pn]); R ic0 = p[0].inverse(); _multiply_1(tmpp.get(), p, pn, ic0); _inverse_power_series(res, resn, tmpp.get(), pn); _multiply_1(res, resn, ic0); return; } unique_ptr ws(new R[resn * 4]); R *tmp1 = ws.get(), *tmp2 = tmp1 + resn * 2; _fill_zero(res, resn); res[0] = p[0]; int curn = 1; while (curn < resn) { int nextn = std::min(resn, curn * 2); _square_select_method(tmp1, res, curn); _multiply_select_method(tmp2, tmp1, std::min(nextn, curn * 2 - 1), p, std::min(nextn, pn)); _multiply_power_of_two(res, res, curn, 1); _subtract(res, tmp2, nextn); curn = nextn; } } void Polynomial::_precompute_reverse_inverse(R *res, int resn, const R *p, int pn) { unique_ptr ws(new R[pn]); R *tmp = ws.get(); _reverse(tmp, p, pn); _inverse_power_series(res, resn, tmp, pn); } void Polynomial::_divide_precomputed_inverse(R *res, int resn, const R *revp, int pn, const R *inv) { unique_ptr ws(new R[pn + resn]); R *tmp = ws.get(); _multiply_select_method(tmp, revp, pn, inv, resn); _reverse(res, tmp, resn); } void Polynomial::_divide_remainder_precomputed_inverse(R *quot, R *rem, const R *p, int pn, const R *q, int qn, const R *inv) { if (pn < qn) { _copy(rem, p, pn); _fill_zero(rem + pn, qn - 1 - pn); return; } assert(qn > 0); assert(q[qn - 1] == OneR()); if (qn == 1) return; int quotn = pn - qn + 1; int rn = qn - 1, tn = std::min(quotn, rn), un = tn + rn; unique_ptr ws(new R[pn + un + (quot != NULL ? 0 : quotn)]); R *revp = ws.get(), *quotmul = revp + pn; if (quot == NULL) quot = quotmul + un; _reverse(revp, p, pn); _divide_precomputed_inverse(quot, quotn, revp, pn, inv); _multiply_select_method(quotmul, q, rn, quot, tn); _subtract(rem, p, rn, quotmul, rn); } } vector fact, factinv; void nCr_computeFactinv(int N) { N = min(N, (int)mint::getMod() - 1); fact.resize(N + 1); factinv.resize(N + 1); fact[0] = 1; rer(i, 1, N) fact[i] = fact[i - 1] * i; factinv[N] = fact[N].inverse(); for (int i = N; i >= 1; i --) factinv[i - 1] = factinv[i] * i; } mint nCr(int n, int r) { return r > n ? 0 : fact[n] * factinv[n - r] * factinv[r]; } mint catalan_number(int n) { return n == 0 ? 1 : nCr(2 * n, n) - nCr(2 * n, n - 1); } int main() { mint::set_mod((int)1e9 + 7); int N; while (~scanf("%d", &N)) { nCr_computeFactinv(N * 2); mint ans; const int K = N / 2 + 1; using Polynomial = mod_polynomial::Polynomial; Polynomial poly, catalan; rep(k, K) poly.set(k, nCr(N + k * 2, k)); catalan.set(0, 1); rep(k, K) catalan.set(k + 1, -catalan_number(k) * 2); const auto prod = poly * catalan; rep(k, K) ans += prod.get(k); printf("%d\n", ans.get()); } return 0; }