#if __INCLUDE_LEVEL__ #include #include //#define int ll using mint=atcoder::static_modint<1000000007>; //using mint=modint; atcoder::modint::set_mod(int m); #endif #if !__INCLUDE_LEVEL__ #include __FILE__ signed main(){ //cout<sync_with_stdio(0); //int start_clock=clock(); //srand((unsigned)time(NULL)); //your code here! int n;cin>>n; vi a(n);cin>>a; vi t(109); rep(i,n) t[a[i]]++; FPSFFT f={1}; rep(i,108) f*=FPSFFT{1,t[i]}; ans(f[3].val()); } #else //template using namespace std; using ull = unsigned long long; using ll = long long; using vi = vector; using vl = vector; using vll = vector; using vb = vector; using vf = vector; using vd = vector; using vvi = vector; using vvl = vector; using vvll = vector; using vvf = vector; using vvd = vector; using vvvi = vector; using vvvd = vector; using vs = vector; using pii = pair; using vpii = vector; using vm=vector; using vvm=vector; using vvvm=vector; #define ERROR(...) {cerr<<"ERROR @ LINE "<<__LINE__<=0;(i)--) #define REPD3(i,a,n) for(int i=(int)(n)-1;(i)>=(int)(a);(i)--) #define repd(...) REPD_OVERLOAD(__VA_ARGS__, REPD3, REPD2, ERROR)(__VA_ARGS__) template inline T chmax(T &a,const T &b){if(a inline T chmin(T &a,const T &b){if(b inline T gcd(T a,T b){return b?gcd(b,a%b):a;} template inline ll lcm(T a,T b){return (log2(a)-log2(gcd(a,b))+log2(b)<62)?(a/gcd(a,b)*b dx={1,0,-1,0}; const vector dy={0,1,0,-1}; constexpr double pi=3.141592653589793; constexpr double PI=3.141592653589793; #define DEBUG(x) cerr<<__LINE__<<#x<<": "< inline void SORT(vector& vec){sort(vec.begin(),vec.end());} template inline void RSORT(vector& vec){sort(vec.begin(),vec.end(),greater());} template inline void ans(T res) {cout< inline void yesno(T b) {ans((bool)(b)?"Yes":"No");} inline void yes(){yesno(1);} inline void no(){yesno(0);} ostream &operator<<(ostream &os,const mint &x){ os< ostream &operator<<(ostream &os,const pair &p){ os< istream &operator>>(istream& is,pair& p){ is>>p.first>>p.second; return is; } template ostream &operator<<(ostream &os,const vector &vec){ for(int i=0;i<(int)vec.size();i++){os< istream &operator>>(istream& is,vector& vec){ for(int i=0;i<(int)vec.size();i++){is>>vec[i];}return is; } template void operator+=(vector& vec, int n){ for(T& e:vec) e+=n; } template void operator*=(vector& vec, int n){ for(T& e:vec) e*=n; } template vector operator+(const vector& vec0, const vector vec1){ int n=vec0.size(); if(n!=vec1.size()){cerr<<"ERROR: oparator*(const vector&, const vector&): v0.size()!=v1.size()"< res; for(int i=0;i T operator*(const vector& vec0, const vector vec1){ int n=vec0.size(); if(n!=vec1.size()){cerr<<"ERROR: oparator*(const vector&, const vector&): v0.size()!=v1.size()"< vector make_v(size_t a,T b){return vector(a,b);} template auto make_v(size_t a,Ts... ts){return vector(a,make_v(ts...));} vi range(int N){vi res(N); for(int i=0;i vector range(vector& v){return v;} #define FOR_PERM(v,n) for(auto (v)=range(n); (v).size()!=0; next_permutation((v).begin(),(v).end()) || ((v)={},0)) vvi forfor(vi v, int depth, const function& fbegin, const function& fend, int prev, int sum){ if(depth==0) return {v}; int a=fbegin(prev,sum); int b=fend(prev,sum); vvi res; for(int i=a;i)を返す template vector primes(T N) { vector res; vector isprime(N+1,true); isprime[0]=isprime[1]=false; for(T p=2;p T pow_mod(T A, T N, T M) { T res = 1 % M; A %= M; while (N) { if (N & 1) res = (res * A) % M; A = (A * A) % M; N >>= 1; } return res; } bool MillerRabin(long long N, vector A) { long long s = 0, d = N - 1; while (d % 2 == 0) { ++s; d >>= 1; } for (auto a : A) { if (N <= a) return true; long long t, x = pow_mod<__int128_t>(a, d, N); if (x != 1) { for (t = 0; t < s; ++t) { if (x == N - 1) break; x = __int128_t(x) * x % N; } if (t == s) return false; } } return true; } bool is_prime(long long N) { if (N <= 1) return false; if (N == 2) return true; if (N % 2 == 0) return false; if (N < 4759123141LL) return MillerRabin(N, {2, 7, 61}); else return MillerRabin(N, {2, 325, 9375, 28178, 450775, 9780504, 1795265022}); } } using IsPrime::is_prime; //素因数分解 template vector> prime_factories(T N){ vector> res; for(T a=2;a*a<=N;a++){ if(N%a!=0)continue; int ex=0; while(N%a==0){ ex++; N/=a; } res.pb({a,ex}); } if(N!=1)res.pb({N,1}); return res; } // 二分探索: // !f(i-1) && f(i) となるようなiのうちいずれか1つを返すか、 // f(0)==f(N) のとき f(0) なら 0, !f(0) なら N を返す // 制約 : f(0) ⇒ f(N) template T binarySearch(T N, function f){ T min=-1, max=N; for(;max-min>1;){ T mid=(min+max)/2; if(f(mid)) max=mid; else min=mid; } return max; } // 有理数型 template class fraction{ public: // 分母, 分子 T top, bottom; fraction(T top_,T bottom_){top=top_;bottom=bottom_;if(bottom==0) ERROR("fraction constractor: 0-devided error");} friend bool operator<(fraction const& a,fraction const& b){ if(a.bottom>0!=b.bottom>0) return (ll)a.top*(ll)b.bottom<(ll)b.top*(ll)a.bottom; else return (ll)a.top*(ll)b.bottom>(ll)b.top*(ll)a.bottom; } friend bool operator>(fraction const& a,fraction const& b){ if(a.bottom>0!=b.bottom>0) return (ll)a.top*(ll)b.bottom>(ll)b.top*(ll)a.bottom; else return (ll)a.top*(ll)b.bottom<(ll)b.top*(ll)a.bottom; } friend bool operator!=(fraction const& a,fraction const& b){return a>b||a=(fraction const& a,fraction const& b){return a>b||a==b;} friend bool operator<=(fraction const& a,fraction const& b){return a T L1_norm(T x0,T y0,T x1,T y1){return abs(x0-x1)+abs(y0-y1);} // ユークリッド距離 template double L2_norm(T x0,T y0,T x1,T y1){T dx=x0-x1,dy=y0-y1; return sqrt(dx*dx+dy*dy);} // kitamasa法 O(k^2*logk) // 漸化式 a[n+k]=sigma{0<=i T kitamasa(const vector& a,const vector& d,U n){ int k = a.size(); if(n < k) return a[n]; function(U)> dfs=[&a,&d,k,&dfs](U n){ if(n == k) return d; vector res(k); if(n & 1 || n < k * 2){ vector x = dfs(n - 1); for(int i = 0; i < k; ++i) res[i] = d[i] * x[k - 1]; for(int i = 0; i + 1 < k; ++i) res[i + 1] += x[i]; } else{ vector> x(k, vector(k)); x[0] = dfs(n >> 1); for(int i = 0; i + 1 < k; ++i){ for(int j = 0; j < k; ++j) x[i + 1][j] = d[j] * x[i][k - 1]; for(int j = 0; j + 1 < k; ++j) x[i + 1][j + 1] += x[i][j]; } for(int i = 0; i < k; ++i){ for(int j = 0; j < k; ++j){ res[j] += x[0][i] * x[i][j]; } } } return res; }; // a_n を求める vector x = dfs(n); T res = 0; for(int i = 0; i < k; ++i) res += x[i] * a[i]; return res; } // cf. https://ei1333.github.io/library/ namespace luzhiled{ #line 2 "math/fps/formal-power-series-friendly-ntt.hpp" #line 1 "math/fft/number-theoretic-transform-friendly-mod-int.hpp" /** * @brief Number Theoretic Transform Friendly ModInt */ template struct NumberTheoreticTransformFriendlyModInt { static vector roots, iroots, rate3, irate3; static int max_base; NumberTheoreticTransformFriendlyModInt() = default; static void init() { if (roots.empty()) { const unsigned mod = Mint::mod(); assert(mod >= 3 && mod % 2 == 1); auto tmp = mod - 1; max_base = 0; while (tmp % 2 == 0) tmp >>= 1, max_base++; Mint root = 2; while (root.pow((mod - 1) >> 1) == 1) { root += 1; } assert(root.pow(mod - 1) == 1); roots.resize(max_base + 1); iroots.resize(max_base + 1); rate3.resize(max_base + 1); irate3.resize(max_base + 1); roots[max_base] = root.pow((mod - 1) >> max_base); iroots[max_base] = Mint(1) / roots[max_base]; for (int i = max_base - 1; i >= 0; i--) { roots[i] = roots[i + 1] * roots[i + 1]; iroots[i] = iroots[i + 1] * iroots[i + 1]; } { Mint prod = 1, iprod = 1; for (int i = 0; i <= max_base - 3; i++) { rate3[i] = roots[i + 3] * prod; irate3[i] = iroots[i + 3] * iprod; prod *= iroots[i + 3]; iprod *= roots[i + 3]; } } } } static void ntt(vector &a) { init(); const int n = (int)a.size(); assert((n & (n - 1)) == 0); int h = __builtin_ctz(n); assert(h <= max_base); int len = 0; Mint imag = roots[2]; if (h & 1) { int p = 1 << (h - 1); Mint rot = 1; for (int i = 0; i < p; i++) { auto r = a[i + p]; a[i + p] = a[i] - r; a[i] += r; } len++; } for (; len + 1 < h; len += 2) { int p = 1 << (h - len - 2); { // s = 0 for (int i = 0; i < p; i++) { auto a0 = a[i]; auto a1 = a[i + p]; auto a2 = a[i + 2 * p]; auto a3 = a[i + 3 * p]; auto a1na3imag = (a1 - a3) * imag; auto a0a2 = a0 + a2; auto a1a3 = a1 + a3; auto a0na2 = a0 - a2; a[i] = a0a2 + a1a3; a[i + 1 * p] = a0a2 - a1a3; a[i + 2 * p] = a0na2 + a1na3imag; a[i + 3 * p] = a0na2 - a1na3imag; } } Mint rot = rate3[0]; for (int s = 1; s < (1 << len); s++) { int offset = s << (h - len); Mint rot2 = rot * rot; Mint rot3 = rot2 * rot; for (int i = 0; i < p; i++) { auto a0 = a[i + offset]; auto a1 = a[i + offset + p] * rot; auto a2 = a[i + offset + 2 * p] * rot2; auto a3 = a[i + offset + 3 * p] * rot3; auto a1na3imag = (a1 - a3) * imag; auto a0a2 = a0 + a2; auto a1a3 = a1 + a3; auto a0na2 = a0 - a2; a[i + offset] = a0a2 + a1a3; a[i + offset + 1 * p] = a0a2 - a1a3; a[i + offset + 2 * p] = a0na2 + a1na3imag; a[i + offset + 3 * p] = a0na2 - a1na3imag; } rot *= rate3[__builtin_ctz(~s)]; } } } static void intt(vector &a, bool f = true) { init(); const int n = (int)a.size(); assert((n & (n - 1)) == 0); int h = __builtin_ctz(n); assert(h <= max_base); int len = h; Mint iimag = iroots[2]; for (; len > 1; len -= 2) { int p = 1 << (h - len); { // s = 0 for (int i = 0; i < p; i++) { auto a0 = a[i]; auto a1 = a[i + 1 * p]; auto a2 = a[i + 2 * p]; auto a3 = a[i + 3 * p]; auto a2na3iimag = (a2 - a3) * iimag; auto a0na1 = a0 - a1; auto a0a1 = a0 + a1; auto a2a3 = a2 + a3; a[i] = a0a1 + a2a3; a[i + 1 * p] = (a0na1 + a2na3iimag); a[i + 2 * p] = (a0a1 - a2a3); a[i + 3 * p] = (a0na1 - a2na3iimag); } } Mint irot = irate3[0]; for (int s = 1; s < (1 << (len - 2)); s++) { int offset = s << (h - len + 2); Mint irot2 = irot * irot; Mint irot3 = irot2 * irot; for (int i = 0; i < p; i++) { auto a0 = a[i + offset]; auto a1 = a[i + offset + 1 * p]; auto a2 = a[i + offset + 2 * p]; auto a3 = a[i + offset + 3 * p]; auto a2na3iimag = (a2 - a3) * iimag; auto a0na1 = a0 - a1; auto a0a1 = a0 + a1; auto a2a3 = a2 + a3; a[i + offset] = a0a1 + a2a3; a[i + offset + 1 * p] = (a0na1 + a2na3iimag) * irot; a[i + offset + 2 * p] = (a0a1 - a2a3) * irot2; a[i + offset + 3 * p] = (a0na1 - a2na3iimag) * irot3; } irot *= irate3[__builtin_ctz(~s)]; } } if (len >= 1) { int p = 1 << (h - 1); for (int i = 0; i < p; i++) { auto ajp = a[i] - a[i + p]; a[i] += a[i + p]; a[i + p] = ajp; } } if (f) { Mint inv_sz = Mint(1) / n; for (int i = 0; i < n; i++) a[i] *= inv_sz; } } static vector multiply(vector a, vector b) { int need = a.size() + b.size() - 1; int nbase = 1; while ((1 << nbase) < need) nbase++; int sz = 1 << nbase; a.resize(sz, 0); b.resize(sz, 0); ntt(a); ntt(b); Mint inv_sz = Mint(1) / sz; for (int i = 0; i < sz; i++) a[i] *= b[i] * inv_sz; intt(a, false); a.resize(need); return a; } }; template vector NumberTheoreticTransformFriendlyModInt::roots = vector(); template vector NumberTheoreticTransformFriendlyModInt::iroots = vector(); template vector NumberTheoreticTransformFriendlyModInt::rate3 = vector(); template vector NumberTheoreticTransformFriendlyModInt::irate3 = vector(); template int NumberTheoreticTransformFriendlyModInt::max_base = 0; #line 4 "math/fps/formal-power-series-friendly-ntt.hpp" template struct FormalPowerSeriesFriendlyNTT : vector { using vector::vector; using P = FormalPowerSeriesFriendlyNTT; using NTT = NumberTheoreticTransformFriendlyModInt; P pre(int deg) const { return P(begin(*this), begin(*this) + min((int)this->size(), deg)); } P rev(int deg = -1) const { P ret(*this); if (deg != -1) ret.resize(deg, T(0)); reverse(begin(ret), end(ret)); return ret; } void shrink() { while (this->size() && this->back() == T(0)) this->pop_back(); } P operator+(const P &r) const { return P(*this) += r; } P operator+(const T &v) const { return P(*this) += v; } P operator-(const P &r) const { return P(*this) -= r; } P operator-(const T &v) const { return P(*this) -= v; } P operator*(const P &r) const { return P(*this) *= r; } P operator*(const T &v) const { return P(*this) *= v; } P operator/(const P &r) const { return P(*this) /= r; } P operator%(const P &r) const { return P(*this) %= r; } P &operator+=(const P &r) { if (r.size() > this->size()) this->resize(r.size()); for (int i = 0; i < (int)r.size(); i++) (*this)[i] += r[i]; return *this; } P &operator-=(const P &r) { if (r.size() > this->size()) this->resize(r.size()); for (int i = 0; i < (int)r.size(); i++) (*this)[i] -= r[i]; return *this; } // https://judge.yosupo.jp/problem/convolution_mod P &operator*=(const P &r) { if (this->empty() || r.empty()) { this->clear(); return *this; } auto ret = NTT::multiply(*this, r); return *this = {begin(ret), end(ret)}; } P &operator/=(const P &r) { if (this->size() < r.size()) { this->clear(); return *this; } int n = this->size() - r.size() + 1; return *this = (rev().pre(n) * r.rev().inv(n)).pre(n).rev(n); } P &operator%=(const P &r) { *this -= *this / r * r; shrink(); return *this; } // https://judge.yosupo.jp/problem/division_of_polynomials pair div_mod(const P &r) { P q = *this / r; P x = *this - q * r; x.shrink(); return make_pair(q, x); } P operator-() const { P ret(this->size()); for (int i = 0; i < (int)this->size(); i++) ret[i] = -(*this)[i]; return ret; } P &operator+=(const T &r) { if (this->empty()) this->resize(1); (*this)[0] += r; return *this; } P &operator-=(const T &r) { if (this->empty()) this->resize(1); (*this)[0] -= r; return *this; } P &operator*=(const T &v) { for (int i = 0; i < (int)this->size(); i++) (*this)[i] *= v; return *this; } P dot(P r) const { P ret(min(this->size(), r.size())); for (int i = 0; i < (int)ret.size(); i++) ret[i] = (*this)[i] * r[i]; return ret; } P operator>>(int sz) const { if ((int)this->size() <= sz) return {}; P ret(*this); ret.erase(ret.begin(), ret.begin() + sz); return ret; } P operator<<(int sz) const { P ret(*this); ret.insert(ret.begin(), sz, T(0)); return ret; } T operator()(T x) const { T r = 0, w = 1; for (auto &v : *this) { r += w * v; w *= x; } return r; } P diff() const { const int n = (int)this->size(); P ret(max(0, n - 1)); for (int i = 1; i < n; i++) ret[i - 1] = (*this)[i] * T(i); return ret; } P integral() const { const int n = (int)this->size(); P ret(n + 1); ret[0] = T(0); for (int i = 0; i < n; i++) ret[i + 1] = (*this)[i] / T(i + 1); return ret; } // https://judge.yosupo.jp/problem/inv_of_formal_power_series // F(0) must not be 0 P inv(int deg = -1) const { assert(((*this)[0]) != T(0)); const int n = (int)this->size(); if (deg == -1) deg = n; P res(deg); res[0] = {T(1) / (*this)[0]}; for (int d = 1; d < deg; d <<= 1) { P f(2 * d), g(2 * d); for (int j = 0; j < min(n, 2 * d); j++) f[j] = (*this)[j]; for (int j = 0; j < d; j++) g[j] = res[j]; NTT::ntt(f); NTT::ntt(g); f = f.dot(g); NTT::intt(f); for (int j = 0; j < d; j++) f[j] = 0; NTT::ntt(f); for (int j = 0; j < 2 * d; j++) f[j] *= g[j]; NTT::intt(f); for (int j = d; j < min(2 * d, deg); j++) res[j] = -f[j]; } return res; } // https://judge.yosupo.jp/problem/log_of_formal_power_series // F(0) must be 1 P log(int deg = -1) const { assert((*this)[0] == T(1)); const int n = (int)this->size(); if (deg == -1) deg = n; return (this->diff() * this->inv(deg)).pre(deg - 1).integral(); } // https://judge.yosupo.jp/problem/sqrt_of_formal_power_series P sqrt( int deg = -1, const function &get_sqrt = [](T) { return T(1); }) const { const int n = (int)this->size(); if (deg == -1) deg = n; if ((*this)[0] == T(0)) { for (int i = 1; i < n; i++) { if ((*this)[i] != T(0)) { if (i & 1) return {}; if (deg - i / 2 <= 0) break; auto ret = (*this >> i).sqrt(deg - i / 2, get_sqrt); if (ret.empty()) return {}; ret = ret << (i / 2); if ((int)ret.size() < deg) ret.resize(deg, T(0)); return ret; } } return P(deg, 0); } auto sqr = T(get_sqrt((*this)[0])); if (sqr * sqr != (*this)[0]) return {}; P ret{sqr}; T inv2 = T(1) / T(2); for (int i = 1; i < deg; i <<= 1) { ret = (ret + pre(i << 1) * ret.inv(i << 1)) * inv2; } return ret.pre(deg); } P sqrt(const function &get_sqrt, int deg = -1) const { return sqrt(deg, get_sqrt); } // https://judge.yosupo.jp/problem/exp_of_formal_power_series // F(0) must be 0 P exp(int deg = -1) const { if (deg == -1) deg = this->size(); assert((*this)[0] == T(0)); P inv; inv.reserve(deg + 1); inv.push_back(T(0)); inv.push_back(T(1)); auto inplace_integral = [&](P &F) -> void { const int n = (int)F.size(); auto mod = T::mod(); while ((int)inv.size() <= n) { int i = inv.size(); inv.push_back((-inv[mod % i]) * (mod / i)); } F.insert(begin(F), T(0)); for (int i = 1; i <= n; i++) F[i] *= inv[i]; }; auto inplace_diff = [](P &F) -> void { if (F.empty()) return; F.erase(begin(F)); T coeff = 1, one = 1; for (int i = 0; i < (int)F.size(); i++) { F[i] *= coeff; coeff += one; } }; P b{1, 1 < (int)this->size() ? (*this)[1] : 0}, c{1}, z1, z2{1, 1}; for (int m = 2; m < deg; m *= 2) { auto y = b; y.resize(2 * m); NTT::ntt(y); z1 = z2; P z(m); for (int i = 0; i < m; ++i) z[i] = y[i] * z1[i]; NTT::intt(z); fill(begin(z), begin(z) + m / 2, T(0)); NTT::ntt(z); for (int i = 0; i < m; ++i) z[i] *= -z1[i]; NTT::intt(z); c.insert(end(c), begin(z) + m / 2, end(z)); z2 = c; z2.resize(2 * m); NTT::ntt(z2); P x(begin(*this), begin(*this) + min(this->size(), m)); inplace_diff(x); x.push_back(T(0)); NTT::ntt(x); for (int i = 0; i < m; ++i) x[i] *= y[i]; NTT::intt(x); x -= b.diff(); x.resize(2 * m); for (int i = 0; i < m - 1; ++i) x[m + i] = x[i], x[i] = T(0); NTT::ntt(x); for (int i = 0; i < 2 * m; ++i) x[i] *= z2[i]; NTT::intt(x); x.pop_back(); inplace_integral(x); for (int i = m; i < min(this->size(), 2 * m); ++i) x[i] += (*this)[i]; fill(begin(x), begin(x) + m, T(0)); NTT::ntt(x); for (int i = 0; i < 2 * m; ++i) x[i] *= y[i]; NTT::intt(x); b.insert(end(b), begin(x) + m, end(x)); } return P{begin(b), begin(b) + deg}; } // https://judge.yosupo.jp/problem/pow_of_formal_power_series P pow(int64_t k, int deg = -1) const { const int n = (int)this->size(); if (deg == -1) deg = n; if (k == 0) { P ret(deg, T(0)); ret[0] = T(1); return ret; } for (int i = 0; i < n; i++) { if (i * k > deg) return P(deg, T(0)); if ((*this)[i] != T(0)) { T rev = T(1) / (*this)[i]; P ret = (((*this * rev) >> i).log() * k).exp() * ((*this)[i].pow(k)); ret = (ret << (i * k)).pre(deg); if ((int)ret.size() < deg) ret.resize(deg, T(0)); return ret; } } return *this; } P mod_pow(int64_t k, P g) const { P modinv = g.rev().inv(); auto get_div = [&](P base) { if (base.size() < g.size()) { base.clear(); return base; } int n = base.size() - g.size() + 1; return (base.rev().pre(n) * modinv.pre(n)).pre(n).rev(n); }; P x(*this), ret{1}; while (k > 0) { if (k & 1) { ret *= x; ret -= get_div(ret) * g; ret.shrink(); } x *= x; x -= get_div(x) * g; x.shrink(); k >>= 1; } return ret; } // https://judge.yosupo.jp/problem/polynomial_taylor_shift P taylor_shift(T c) const { int n = (int)this->size(); vector fact(n), rfact(n); fact[0] = rfact[0] = T(1); for (int i = 1; i < n; i++) fact[i] = fact[i - 1] * T(i); rfact[n - 1] = T(1) / fact[n - 1]; for (int i = n - 1; i > 1; i--) rfact[i - 1] = rfact[i] * T(i); P p(*this); for (int i = 0; i < n; i++) p[i] *= fact[i]; p = p.rev(); P bs(n, T(1)); for (int i = 1; i < n; i++) bs[i] = bs[i - 1] * c * rfact[i] * fact[i - 1]; p = (p * bs).pre(n); p = p.rev(); for (int i = 0; i < n; i++) p[i] *= rfact[i]; return p; } }; template using FPSNTT = FormalPowerSeriesFriendlyNTT; #line 2 "math/fps/formal-power-series.hpp" #line 1 "math/fft/fast-fourier-transform.hpp" namespace FastFourierTransform { using real = double; struct C { real x, y; C() : x(0), y(0) {} C(real x, real y) : x(x), y(y) {} inline C operator+(const C &c) const { return C(x + c.x, y + c.y); } inline C operator-(const C &c) const { return C(x - c.x, y - c.y); } inline C operator*(const C &c) const { return C(x * c.x - y * c.y, x * c.y + y * c.x); } inline C conj() const { return C(x, -y); } }; const real PI = acosl(-1); int base = 1; vector rts = {{0, 0}, {1, 0}}; vector rev = {0, 1}; void ensure_base(int nbase) { if (nbase <= base) return; rev.resize(1 << nbase); rts.resize(1 << nbase); for (int i = 0; i < (1 << nbase); i++) { rev[i] = (rev[i >> 1] >> 1) + ((i & 1) << (nbase - 1)); } while (base < nbase) { real angle = PI * 2.0 / (1 << (base + 1)); for (int i = 1 << (base - 1); i < (1 << base); i++) { rts[i << 1] = rts[i]; real angle_i = angle * (2 * i + 1 - (1 << base)); rts[(i << 1) + 1] = C(cos(angle_i), sin(angle_i)); } ++base; } } void fft(vector &a, int n) { assert((n & (n - 1)) == 0); int zeros = __builtin_ctz(n); ensure_base(zeros); int shift = base - zeros; for (int i = 0; i < n; i++) { if (i < (rev[i] >> shift)) { swap(a[i], a[rev[i] >> shift]); } } for (int k = 1; k < n; k <<= 1) { for (int i = 0; i < n; i += 2 * k) { for (int j = 0; j < k; j++) { C z = a[i + j + k] * rts[j + k]; a[i + j + k] = a[i + j] - z; a[i + j] = a[i + j] + z; } } } } vector multiply(const vector &a, const vector &b) { int need = (int)a.size() + (int)b.size() - 1; int nbase = 1; while ((1 << nbase) < need) nbase++; ensure_base(nbase); int sz = 1 << nbase; vector fa(sz); for (int i = 0; i < sz; i++) { int x = (i < (int)a.size() ? a[i] : 0); int y = (i < (int)b.size() ? b[i] : 0); fa[i] = C(x, y); } fft(fa, sz); C r(0, -0.25 / (sz >> 1)), s(0, 1), t(0.5, 0); for (int i = 0; i <= (sz >> 1); i++) { int j = (sz - i) & (sz - 1); C z = (fa[j] * fa[j] - (fa[i] * fa[i]).conj()) * r; fa[j] = (fa[i] * fa[i] - (fa[j] * fa[j]).conj()) * r; fa[i] = z; } for (int i = 0; i < (sz >> 1); i++) { C A0 = (fa[i] + fa[i + (sz >> 1)]) * t; C A1 = (fa[i] - fa[i + (sz >> 1)]) * t * rts[(sz >> 1) + i]; fa[i] = A0 + A1 * s; } fft(fa, sz >> 1); vector ret(need); for (int i = 0; i < need; i++) { ret[i] = llround(i & 1 ? fa[i >> 1].y : fa[i >> 1].x); } return ret; } }; // namespace FastFourierTransform #line 2 "math/fft/arbitrary-mod-convolution.hpp" /* * @brief Arbitrary Mod Convolution(任意mod畳み込み) */ template struct ArbitraryModConvolution { using real = FastFourierTransform::real; using C = FastFourierTransform::C; ArbitraryModConvolution() = default; static vector multiply(const vector &a, const vector &b, int need = -1) { if (need == -1) need = a.size() + b.size() - 1; int nbase = 0; while ((1 << nbase) < need) nbase++; FastFourierTransform::ensure_base(nbase); int sz = 1 << nbase; vector fa(sz); for (int i = 0; i < a.size(); i++) { fa[i] = C(a[i].val() & ((1 << 15) - 1), a[i].val() >> 15); } fft(fa, sz); vector fb(sz); if (a == b) { fb = fa; } else { for (int i = 0; i < b.size(); i++) { fb[i] = C(b[i].val() & ((1 << 15) - 1), b[i].val() >> 15); } fft(fb, sz); } real ratio = 0.25 / sz; C r2(0, -1), r3(ratio, 0), r4(0, -ratio), r5(0, 1); for (int i = 0; i <= (sz >> 1); i++) { int j = (sz - i) & (sz - 1); C a1 = (fa[i] + fa[j].conj()); C a2 = (fa[i] - fa[j].conj()) * r2; C b1 = (fb[i] + fb[j].conj()) * r3; C b2 = (fb[i] - fb[j].conj()) * r4; if (i != j) { C c1 = (fa[j] + fa[i].conj()); C c2 = (fa[j] - fa[i].conj()) * r2; C d1 = (fb[j] + fb[i].conj()) * r3; C d2 = (fb[j] - fb[i].conj()) * r4; fa[i] = c1 * d1 + c2 * d2 * r5; fb[i] = c1 * d2 + c2 * d1; } fa[j] = a1 * b1 + a2 * b2 * r5; fb[j] = a1 * b2 + a2 * b1; } fft(fa, sz); fft(fb, sz); vector ret(need); for (int i = 0; i < need; i++) { int64_t aa = llround(fa[i].x); int64_t bb = llround(fb[i].x); int64_t cc = llround(fa[i].y); aa = T(aa).val(), bb = T(bb).val(), cc = T(cc).val(); ret[i] = aa + (bb << 15) + (cc << 30); } return ret; } }; #line 4 "math/fps/formal-power-series.hpp" /** * @brief Formal Power Series(形式的冪級数) */ template struct FormalPowerSeries : vector { using vector::vector; using P = FormalPowerSeries; using Conv = ArbitraryModConvolution; P pre(int deg) const { return P(begin(*this), begin(*this) + min((int)this->size(), deg)); } P rev(int deg = -1) const { P ret(*this); if (deg != -1) ret.resize(deg, T(0)); reverse(begin(ret), end(ret)); return ret; } void shrink() { while (this->size() && this->back() == T(0)) this->pop_back(); } P operator+(const P &r) const { return P(*this) += r; } P operator+(const T &v) const { return P(*this) += v; } P operator-(const P &r) const { return P(*this) -= r; } P operator-(const T &v) const { return P(*this) -= v; } P operator*(const P &r) const { return P(*this) *= r; } P operator*(const T &v) const { return P(*this) *= v; } P operator/(const P &r) const { return P(*this) /= r; } P operator%(const P &r) const { return P(*this) %= r; } P &operator+=(const P &r) { if (r.size() > this->size()) this->resize(r.size()); for (int i = 0; i < r.size(); i++) (*this)[i] += r[i]; return *this; } P &operator-=(const P &r) { if (r.size() > this->size()) this->resize(r.size()); for (int i = 0; i < r.size(); i++) (*this)[i] -= r[i]; return *this; } // https://judge.yosupo.jp/problem/convolution_mod P &operator*=(const P &r) { if (this->empty() || r.empty()) { this->clear(); return *this; } auto ret = Conv::multiply(*this, r); return *this = {begin(ret), end(ret)}; } P &operator/=(const P &r) { if (this->size() < r.size()) { this->clear(); return *this; } int n = this->size() - r.size() + 1; return *this = (rev().pre(n) * r.rev().inv(n)).pre(n).rev(n); } P &operator%=(const P &r) { return *this -= *this / r * r; } // https://judge.yosupo.jp/problem/division_of_polynomials pair div_mod(const P &r) { P q = *this / r; return make_pair(q, *this - q * r); } P operator-() const { P ret(this->size()); for (int i = 0; i < this->size(); i++) ret[i] = -(*this)[i]; return ret; } P &operator+=(const T &r) { if (this->empty()) this->resize(1); (*this)[0] += r; return *this; } P &operator-=(const T &r) { if (this->empty()) this->resize(1); (*this)[0] -= r; return *this; } P &operator*=(const T &v) { for (int i = 0; i < this->size(); i++) (*this)[i] *= v; return *this; } P dot(P r) const { P ret(min(this->size(), r.size())); for (int i = 0; i < ret.size(); i++) ret[i] = (*this)[i] * r[i]; return ret; } P operator>>(int sz) const { if (this->size() <= sz) return {}; P ret(*this); ret.erase(ret.begin(), ret.begin() + sz); return ret; } P operator<<(int sz) const { P ret(*this); ret.insert(ret.begin(), sz, T(0)); return ret; } T operator()(T x) const { T r = 0, w = 1; for (auto &v : *this) { r += w * v; w *= x; } return r; } P diff() const { const int n = (int)this->size(); P ret(max(0, n - 1)); for (int i = 1; i < n; i++) ret[i - 1] = (*this)[i] * T(i); return ret; } P integral() const { const int n = (int)this->size(); P ret(n + 1); ret[0] = T(0); for (int i = 0; i < n; i++) ret[i + 1] = (*this)[i] / T(i + 1); return ret; } // https://judge.yosupo.jp/problem/inv_of_formal_power_series // F(0) must not be 0 P inv(int deg = -1) const { assert(((*this)[0]) != T(0)); const int n = (int)this->size(); if (deg == -1) deg = n; P ret({T(1) / (*this)[0]}); for (int i = 1; i < deg; i <<= 1) { ret = (ret + ret - ret * ret * pre(i << 1)).pre(i << 1); } return ret.pre(deg); } // https://judge.yosupo.jp/problem/log_of_formal_power_series // F(0) must be 1 P log(int deg = -1) const { assert((*this)[0] == T(1)); const int n = (int)this->size(); if (deg == -1) deg = n; return (this->diff() * this->inv(deg)).pre(deg - 1).integral(); } // https://judge.yosupo.jp/problem/sqrt_of_formal_power_series P sqrt( int deg = -1, const function &get_sqrt = [](T) { return T(1); }) const { const int n = (int)this->size(); if (deg == -1) deg = n; if ((*this)[0] == T(0)) { for (int i = 1; i < n; i++) { if ((*this)[i] != T(0)) { if (i & 1) return {}; if (deg - i / 2 <= 0) break; auto ret = (*this >> i).sqrt(deg - i / 2, get_sqrt); if (ret.empty()) return {}; ret = ret << (i / 2); if (ret.size() < deg) ret.resize(deg, T(0)); return ret; } } return P(deg, 0); } auto sqr = T(get_sqrt((*this)[0])); if (sqr * sqr != (*this)[0]) return {}; P ret{sqr}; T inv2 = T(1) / T(2); for (int i = 1; i < deg; i <<= 1) { ret = (ret + pre(i << 1) * ret.inv(i << 1)) * inv2; } return ret.pre(deg); } P sqrt(const function &get_sqrt, int deg = -1) const { return sqrt(deg, get_sqrt); } // https://judge.yosupo.jp/problem/exp_of_formal_power_series // F(0) must be 0 P exp(int deg = -1) const { if (deg == -1) deg = this->size(); assert((*this)[0] == T(0)); const int n = (int)this->size(); if (deg == -1) deg = n; P ret({T(1)}); for (int i = 1; i < deg; i <<= 1) { ret = (ret * (pre(i << 1) + T(1) - ret.log(i << 1))).pre(i << 1); } return ret.pre(deg); } // https://judge.yosupo.jp/problem/pow_of_formal_power_series P pow(int64_t k, int deg = -1) const { const int n = (int)this->size(); if (deg == -1) deg = n; if (k == 0) { P ret(deg, T(0)); ret[0] = T(1); return ret; } for (int i = 0; i < n; i++) { if (i * k > deg) return P(deg, T(0)); if ((*this)[i] != T(0)) { T rev = T(1) / (*this)[i]; P ret = (((*this * rev) >> i).log() * k).exp() * ((*this)[i].pow(k)); ret = (ret << (i * k)).pre(deg); if (ret.size() < deg) ret.resize(deg, T(0)); return ret; } } return *this; } // https://yukicoder.me/problems/no/215 P mod_pow(int64_t k, P g) const { P modinv = g.rev().inv(); auto get_div = [&](P base) { if (base.size() < g.size()) { base.clear(); return base; } int n = base.size() - g.size() + 1; return (base.rev().pre(n) * modinv.pre(n)).pre(n).rev(n); }; P x(*this), ret{1}; while (k > 0) { if (k & 1) { ret *= x; ret -= get_div(ret) * g; ret.shrink(); } x *= x; x -= get_div(x) * g; x.shrink(); k >>= 1; } return ret; } // https://judge.yosupo.jp/problem/polynomial_taylor_shift P taylor_shift(T c) const { int n = (int)this->size(); vector fact(n), rfact(n); fact[0] = rfact[0] = T(1); for (int i = 1; i < n; i++) fact[i] = fact[i - 1] * T(i); rfact[n - 1] = T(1) / fact[n - 1]; for (int i = n - 1; i > 1; i--) rfact[i - 1] = rfact[i] * T(i); P p(*this); for (int i = 0; i < n; i++) p[i] *= fact[i]; p = p.rev(); P bs(n, T(1)); for (int i = 1; i < n; i++) bs[i] = bs[i - 1] * c * rfact[i] * fact[i - 1]; p = (p * bs).pre(n); p = p.rev(); for (int i = 0; i < n; i++) p[i] *= rfact[i]; return p; } }; template using FPSFFT = FormalPowerSeries; }; using luzhiled::FPSNTT; using luzhiled::FPSFFT; //template ends here //main() is at the top of this file #endif