#line 1 "/home/maspy/compro/library/my_template.hpp" #if defined(LOCAL) #include #else #pragma GCC optimize("Ofast") #pragma GCC optimize("unroll-loops") #include using namespace std; using ll = long long; using u32 = unsigned int; using u64 = unsigned long long; using i128 = __int128; using u128 = unsigned __int128; using f128 = __float128; template constexpr T infty = 0; template <> constexpr int infty = 1'000'000'000; template <> constexpr ll infty = ll(infty) * infty * 2; template <> constexpr u32 infty = infty; template <> constexpr u64 infty = infty; template <> constexpr i128 infty = i128(infty) * infty; template <> constexpr double infty = infty; template <> constexpr long double infty = infty; using pi = pair; using vi = vector; template using vc = vector; template using vvc = vector>; template using vvvc = vector>; template using vvvvc = vector>; template using vvvvvc = vector>; template using pq = priority_queue; template using pqg = priority_queue, greater>; #define vv(type, name, h, ...) \ vector> name(h, vector(__VA_ARGS__)) #define vvv(type, name, h, w, ...) \ vector>> name( \ h, vector>(w, vector(__VA_ARGS__))) #define vvvv(type, name, a, b, c, ...) \ vector>>> name( \ a, vector>>( \ b, vector>(c, vector(__VA_ARGS__)))) // https://trap.jp/post/1224/ #define FOR1(a) for (ll _ = 0; _ < ll(a); ++_) #define FOR2(i, a) for (ll i = 0; i < ll(a); ++i) #define FOR3(i, a, b) for (ll i = a; i < ll(b); ++i) #define FOR4(i, a, b, c) for (ll i = a; i < ll(b); i += (c)) #define FOR1_R(a) for (ll i = (a)-1; i >= ll(0); --i) #define FOR2_R(i, a) for (ll i = (a)-1; i >= ll(0); --i) #define FOR3_R(i, a, b) for (ll i = (b)-1; i >= ll(a); --i) #define overload4(a, b, c, d, e, ...) e #define overload3(a, b, c, d, ...) d #define FOR(...) overload4(__VA_ARGS__, FOR4, FOR3, FOR2, FOR1)(__VA_ARGS__) #define FOR_R(...) overload3(__VA_ARGS__, FOR3_R, FOR2_R, FOR1_R)(__VA_ARGS__) #define FOR_subset(t, s) \ for (ll t = (s); t >= 0; t = (t == 0 ? -1 : (t - 1) & (s))) #define all(x) x.begin(), x.end() #define len(x) ll(x.size()) #define elif else if #define eb emplace_back #define mp make_pair #define mt make_tuple #define fi first #define se second #define stoi stoll int popcnt(int x) { return __builtin_popcount(x); } int popcnt(u32 x) { return __builtin_popcount(x); } int popcnt(ll x) { return __builtin_popcountll(x); } int popcnt(u64 x) { return __builtin_popcountll(x); } int popcnt_mod_2(int x) { return __builtin_parity(x); } int popcnt_mod_2(u32 x) { return __builtin_parity(x); } int popcnt_mod_2(ll x) { return __builtin_parityll(x); } int popcnt_mod_2(u64 x) { return __builtin_parityll(x); } // (0, 1, 2, 3, 4) -> (-1, 0, 1, 1, 2) int topbit(int x) { return (x == 0 ? -1 : 31 - __builtin_clz(x)); } int topbit(u32 x) { return (x == 0 ? -1 : 31 - __builtin_clz(x)); } int topbit(ll x) { return (x == 0 ? -1 : 63 - __builtin_clzll(x)); } int topbit(u64 x) { return (x == 0 ? -1 : 63 - __builtin_clzll(x)); } // (0, 1, 2, 3, 4) -> (-1, 0, 1, 0, 2) int lowbit(int x) { return (x == 0 ? -1 : __builtin_ctz(x)); } int lowbit(u32 x) { return (x == 0 ? -1 : __builtin_ctz(x)); } int lowbit(ll x) { return (x == 0 ? -1 : __builtin_ctzll(x)); } int lowbit(u64 x) { return (x == 0 ? -1 : __builtin_ctzll(x)); } template T floor(T a, T b) { return a / b - (a % b && (a ^ b) < 0); } template T ceil(T x, T y) { return floor(x + y - 1, y); } template T bmod(T x, T y) { return x - y * floor(x, y); } template pair divmod(T x, T y) { T q = floor(x, y); return {q, x - q * y}; } template T SUM(const vector &A) { T sm = 0; for (auto &&a: A) sm += a; return sm; } #define MIN(v) *min_element(all(v)) #define MAX(v) *max_element(all(v)) #define LB(c, x) distance((c).begin(), lower_bound(all(c), (x))) #define UB(c, x) distance((c).begin(), upper_bound(all(c), (x))) #define UNIQUE(x) \ sort(all(x)), x.erase(unique(all(x)), x.end()), x.shrink_to_fit() template T POP(deque &que) { T a = que.front(); que.pop_front(); return a; } template T POP(pq &que) { T a = que.top(); que.pop(); return a; } template T POP(pqg &que) { T a = que.top(); que.pop(); return a; } template T POP(vc &que) { T a = que.back(); que.pop_back(); return a; } template ll binary_search(F check, ll ok, ll ng, bool check_ok = true) { if (check_ok) assert(check(ok)); while (abs(ok - ng) > 1) { auto x = (ng + ok) / 2; (check(x) ? ok : ng) = x; } return ok; } template double binary_search_real(F check, double ok, double ng, int iter = 100) { FOR(iter) { double x = (ok + ng) / 2; (check(x) ? ok : ng) = x; } return (ok + ng) / 2; } template inline bool chmax(T &a, const S &b) { return (a < b ? a = b, 1 : 0); } template inline bool chmin(T &a, const S &b) { return (a > b ? a = b, 1 : 0); } // ? は -1 vc s_to_vi(const string &S, char first_char) { vc A(S.size()); FOR(i, S.size()) { A[i] = (S[i] != '?' ? S[i] - first_char : -1); } return A; } template vector cumsum(vector &A, int off = 1) { int N = A.size(); vector B(N + 1); FOR(i, N) { B[i + 1] = B[i] + A[i]; } if (off == 0) B.erase(B.begin()); return B; } // stable sort template vector argsort(const vector &A) { vector ids(len(A)); iota(all(ids), 0); sort(all(ids), [&](int i, int j) { return (A[i] == A[j] ? i < j : A[i] < A[j]); }); return ids; } // A[I[0]], A[I[1]], ... template vc rearrange(const vc &A, const vc &I) { vc B(len(I)); FOR(i, len(I)) B[i] = A[I[i]]; return B; } #endif #line 1 "/home/maspy/compro/library/other/io.hpp" #define FASTIO #include // https://judge.yosupo.jp/submission/21623 namespace fastio { static constexpr uint32_t SZ = 1 << 17; char ibuf[SZ]; char obuf[SZ]; char out[100]; // pointer of ibuf, obuf uint32_t pil = 0, pir = 0, por = 0; struct Pre { char num[10000][4]; constexpr Pre() : num() { for (int i = 0; i < 10000; i++) { int n = i; for (int j = 3; j >= 0; j--) { num[i][j] = n % 10 | '0'; n /= 10; } } } } constexpr pre; inline void load() { memcpy(ibuf, ibuf + pil, pir - pil); pir = pir - pil + fread(ibuf + pir - pil, 1, SZ - pir + pil, stdin); pil = 0; if (pir < SZ) ibuf[pir++] = '\n'; } inline void flush() { fwrite(obuf, 1, por, stdout); por = 0; } void rd(char &c) { do { if (pil + 1 > pir) load(); c = ibuf[pil++]; } while (isspace(c)); } void rd(string &x) { x.clear(); char c; do { if (pil + 1 > pir) load(); c = ibuf[pil++]; } while (isspace(c)); do { x += c; if (pil == pir) load(); c = ibuf[pil++]; } while (!isspace(c)); } template void rd_real(T &x) { string s; rd(s); x = stod(s); } template void rd_integer(T &x) { if (pil + 100 > pir) load(); char c; do c = ibuf[pil++]; while (c < '-'); bool minus = 0; if constexpr (is_signed::value || is_same_v) { if (c == '-') { minus = 1, c = ibuf[pil++]; } } x = 0; while ('0' <= c) { x = x * 10 + (c & 15), c = ibuf[pil++]; } if constexpr (is_signed::value || is_same_v) { if (minus) x = -x; } } void rd(int &x) { rd_integer(x); } void rd(ll &x) { rd_integer(x); } void rd(i128 &x) { rd_integer(x); } void rd(u32 &x) { rd_integer(x); } void rd(u64 &x) { rd_integer(x); } void rd(u128 &x) { rd_integer(x); } void rd(double &x) { rd_real(x); } void rd(long double &x) { rd_real(x); } void rd(f128 &x) { rd_real(x); } template void rd(pair &p) { return rd(p.first), rd(p.second); } template void rd_tuple(T &t) { if constexpr (N < std::tuple_size::value) { auto &x = std::get(t); rd(x); rd_tuple(t); } } template void rd(tuple &tpl) { rd_tuple(tpl); } template void rd(array &x) { for (auto &d: x) rd(d); } template void rd(vc &x) { for (auto &d: x) rd(d); } void read() {} template void read(H &h, T &... t) { rd(h), read(t...); } void wt(const char c) { if (por == SZ) flush(); obuf[por++] = c; } void wt(const string s) { for (char c: s) wt(c); } void wt(const char *s) { size_t len = strlen(s); for (size_t i = 0; i < len; i++) wt(s[i]); } template void wt_integer(T x) { if (por > SZ - 100) flush(); if (x < 0) { obuf[por++] = '-', x = -x; } int outi; for (outi = 96; x >= 10000; outi -= 4) { memcpy(out + outi, pre.num[x % 10000], 4); x /= 10000; } if (x >= 1000) { memcpy(obuf + por, pre.num[x], 4); por += 4; } else if (x >= 100) { memcpy(obuf + por, pre.num[x] + 1, 3); por += 3; } else if (x >= 10) { int q = (x * 103) >> 10; obuf[por] = q | '0'; obuf[por + 1] = (x - q * 10) | '0'; por += 2; } else obuf[por++] = x | '0'; memcpy(obuf + por, out + outi + 4, 96 - outi); por += 96 - outi; } template void wt_real(T x) { ostringstream oss; oss << fixed << setprecision(15) << double(x); string s = oss.str(); wt(s); } void wt(int x) { wt_integer(x); } void wt(ll x) { wt_integer(x); } void wt(i128 x) { wt_integer(x); } void wt(u32 x) { wt_integer(x); } void wt(u64 x) { wt_integer(x); } void wt(u128 x) { wt_integer(x); } void wt(double x) { wt_real(x); } void wt(long double x) { wt_real(x); } void wt(f128 x) { wt_real(x); } template void wt(const pair val) { wt(val.first); wt(' '); wt(val.second); } template void wt_tuple(const T t) { if constexpr (N < std::tuple_size::value) { if constexpr (N > 0) { wt(' '); } const auto x = std::get(t); wt(x); wt_tuple(t); } } template void wt(tuple tpl) { wt_tuple(tpl); } template void wt(const array val) { auto n = val.size(); for (size_t i = 0; i < n; i++) { if (i) wt(' '); wt(val[i]); } } template void wt(const vector val) { auto n = val.size(); for (size_t i = 0; i < n; i++) { if (i) wt(' '); wt(val[i]); } } void print() { wt('\n'); } template void print(Head &&head, Tail &&... tail) { wt(head); if (sizeof...(Tail)) wt(' '); print(forward(tail)...); } // gcc expansion. called automaticall after main. void __attribute__((destructor)) _d() { flush(); } } // namespace fastio using fastio::read; using fastio::print; using fastio::flush; #define INT(...) \ int __VA_ARGS__; \ read(__VA_ARGS__) #define LL(...) \ ll __VA_ARGS__; \ read(__VA_ARGS__) #define U32(...) \ u32 __VA_ARGS__; \ read(__VA_ARGS__) #define U64(...) \ u64 __VA_ARGS__; \ read(__VA_ARGS__) #define STR(...) \ string __VA_ARGS__; \ read(__VA_ARGS__) #define CHAR(...) \ char __VA_ARGS__; \ read(__VA_ARGS__) #define DBL(...) \ double __VA_ARGS__; \ read(__VA_ARGS__) #define VEC(type, name, size) \ vector name(size); \ read(name) #define VV(type, name, h, w) \ vector> name(h, vector(w)); \ read(name) void YES(bool t = 1) { print(t ? "YES" : "NO"); } void NO(bool t = 1) { YES(!t); } void Yes(bool t = 1) { print(t ? "Yes" : "No"); } void No(bool t = 1) { Yes(!t); } void yes(bool t = 1) { print(t ? "yes" : "no"); } void no(bool t = 1) { yes(!t); } #line 3 "main.cpp" #line 2 "/home/maspy/compro/library/mod/modint_common.hpp" struct has_mod_impl { template static auto check(T &&x) -> decltype(x.get_mod(), std::true_type{}); template static auto check(...) -> std::false_type; }; template class has_mod : public decltype(has_mod_impl::check(std::declval())) {}; template mint inv(int n) { static const int mod = mint::get_mod(); static vector dat = {0, 1}; assert(0 <= n); if (n >= mod) n %= mod; while (len(dat) <= n) { int k = len(dat); int q = (mod + k - 1) / k; dat.eb(dat[k * q - mod] * mint::raw(q)); } return dat[n]; } template mint fact(int n) { static const int mod = mint::get_mod(); assert(0 <= n && n < mod); static vector dat = {1, 1}; while (len(dat) <= n) dat.eb(dat[len(dat) - 1] * mint::raw(len(dat))); return dat[n]; } template mint fact_inv(int n) { static vector dat = {1, 1}; if (n < 0) return mint(0); while (len(dat) <= n) dat.eb(dat[len(dat) - 1] * inv(len(dat))); return dat[n]; } template mint fact_invs(Ts... xs) { return (mint(1) * ... * fact_inv(xs)); } template mint multinomial(Head &&head, Tail &&... tail) { return fact(head) * fact_invs(std::forward(tail)...); } template mint C_dense(int n, int k) { static vvc C; static int H = 0, W = 0; auto calc = [&](int i, int j) -> mint { if (i == 0) return (j == 0 ? mint(1) : mint(0)); return C[i - 1][j] + (j ? C[i - 1][j - 1] : 0); }; if (W <= k) { FOR(i, H) { C[i].resize(k + 1); FOR(j, W, k + 1) { C[i][j] = calc(i, j); } } W = k + 1; } if (H <= n) { C.resize(n + 1); FOR(i, H, n + 1) { C[i].resize(W); FOR(j, W) { C[i][j] = calc(i, j); } } H = n + 1; } return C[n][k]; } template mint C(ll n, ll k) { assert(n >= 0); if (k < 0 || n < k) return 0; if constexpr (dense) return C_dense(n, k); if constexpr (!large) return multinomial(n, k, n - k); k = min(k, n - k); mint x(1); FOR(i, k) x *= mint(n - i); return x * fact_inv(k); } template mint C_inv(ll n, ll k) { assert(n >= 0); assert(0 <= k && k <= n); if (!large) return fact_inv(n) * fact(k) * fact(n - k); return mint(1) / C(n, k); } // [x^d](1-x)^{-n} template mint C_negative(ll n, ll d) { assert(n >= 0); if (d < 0) return mint(0); if (n == 0) { return (d == 0 ? mint(1) : mint(0)); } return C(n + d - 1, d); } #line 3 "/home/maspy/compro/library/mod/modint.hpp" template struct modint { static constexpr u32 umod = u32(mod); static_assert(umod < u32(1) << 31); u32 val; static modint raw(u32 v) { modint x; x.val = v; return x; } constexpr modint() : val(0) {} constexpr modint(u32 x) : val(x % umod) {} constexpr modint(u64 x) : val(x % umod) {} constexpr modint(u128 x) : val(x % umod) {} constexpr modint(int x) : val((x %= mod) < 0 ? x + mod : x){}; constexpr modint(ll x) : val((x %= mod) < 0 ? x + mod : x){}; constexpr modint(i128 x) : val((x %= mod) < 0 ? x + mod : x){}; bool operator<(const modint &other) const { return val < other.val; } modint &operator+=(const modint &p) { if ((val += p.val) >= umod) val -= umod; return *this; } modint &operator-=(const modint &p) { if ((val += umod - p.val) >= umod) val -= umod; return *this; } modint &operator*=(const modint &p) { val = u64(val) * p.val % umod; return *this; } modint &operator/=(const modint &p) { *this *= p.inverse(); return *this; } modint operator-() const { return modint::raw(val ? mod - val : u32(0)); } modint operator+(const modint &p) const { return modint(*this) += p; } modint operator-(const modint &p) const { return modint(*this) -= p; } modint operator*(const modint &p) const { return modint(*this) *= p; } modint operator/(const modint &p) const { return modint(*this) /= p; } bool operator==(const modint &p) const { return val == p.val; } bool operator!=(const modint &p) const { return val != p.val; } modint inverse() const { int a = val, b = mod, u = 1, v = 0, t; while (b > 0) { t = a / b; swap(a -= t * b, b), swap(u -= t * v, v); } return modint(u); } modint pow(ll n) const { assert(n >= 0); modint ret(1), mul(val); while (n > 0) { if (n & 1) ret *= mul; mul *= mul; n >>= 1; } return ret; } static constexpr int get_mod() { return mod; } // (n, r), r は 1 の 2^n 乗根 static constexpr pair ntt_info() { if (mod == 120586241) return {20, 74066978}; if (mod == 167772161) return {25, 17}; if (mod == 469762049) return {26, 30}; if (mod == 754974721) return {24, 362}; if (mod == 880803841) return {23, 211}; if (mod == 943718401) return {22, 663003469}; if (mod == 998244353) return {23, 31}; if (mod == 1045430273) return {20, 363}; if (mod == 1051721729) return {20, 330}; if (mod == 1053818881) return {20, 2789}; return {-1, -1}; } static constexpr bool can_ntt() { return ntt_info().fi != -1; } }; #ifdef FASTIO template void rd(modint &x) { fastio::rd(x.val); x.val %= mod; // assert(0 <= x.val && x.val < mod); } template void wt(modint x) { fastio::wt(x.val); } #endif using modint107 = modint<1000000007>; using modint998 = modint<998244353>; #line 2 "/home/maspy/compro/library/graph/base.hpp" template struct Edge { int frm, to; T cost; int id; }; template struct Graph { static constexpr bool is_directed = directed; int N, M; using cost_type = T; using edge_type = Edge; vector edges; vector indptr; vector csr_edges; vc vc_deg, vc_indeg, vc_outdeg; bool prepared; class OutgoingEdges { public: OutgoingEdges(const Graph* G, int l, int r) : G(G), l(l), r(r) {} const edge_type* begin() const { if (l == r) { return 0; } return &G->csr_edges[l]; } const edge_type* end() const { if (l == r) { return 0; } return &G->csr_edges[r]; } private: const Graph* G; int l, r; }; bool is_prepared() { return prepared; } Graph() : N(0), M(0), prepared(0) {} Graph(int N) : N(N), M(0), prepared(0) {} void build(int n) { N = n, M = 0; prepared = 0; edges.clear(); indptr.clear(); csr_edges.clear(); vc_deg.clear(); vc_indeg.clear(); vc_outdeg.clear(); } void add(int frm, int to, T cost = 1, int i = -1) { assert(!prepared); assert(0 <= frm && 0 <= to && to < N); if (i == -1) i = M; auto e = edge_type({frm, to, cost, i}); edges.eb(e); ++M; } #ifdef FASTIO // wt, off void read_tree(bool wt = false, int off = 1) { read_graph(N - 1, wt, off); } void read_graph(int M, bool wt = false, int off = 1) { for (int m = 0; m < M; ++m) { INT(a, b); a -= off, b -= off; if (!wt) { add(a, b); } else { T c; read(c); add(a, b, c); } } build(); } #endif void build() { assert(!prepared); prepared = true; indptr.assign(N + 1, 0); for (auto&& e: edges) { indptr[e.frm + 1]++; if (!directed) indptr[e.to + 1]++; } for (int v = 0; v < N; ++v) { indptr[v + 1] += indptr[v]; } auto counter = indptr; csr_edges.resize(indptr.back() + 1); for (auto&& e: edges) { csr_edges[counter[e.frm]++] = e; if (!directed) csr_edges[counter[e.to]++] = edge_type({e.to, e.frm, e.cost, e.id}); } } OutgoingEdges operator[](int v) const { assert(prepared); return {this, indptr[v], indptr[v + 1]}; } vc deg_array() { if (vc_deg.empty()) calc_deg(); return vc_deg; } pair, vc> deg_array_inout() { if (vc_indeg.empty()) calc_deg_inout(); return {vc_indeg, vc_outdeg}; } int deg(int v) { if (vc_deg.empty()) calc_deg(); return vc_deg[v]; } int in_deg(int v) { if (vc_indeg.empty()) calc_deg_inout(); return vc_indeg[v]; } int out_deg(int v) { if (vc_outdeg.empty()) calc_deg_inout(); return vc_outdeg[v]; } #ifdef FASTIO void debug() { print("Graph"); if (!prepared) { print("frm to cost id"); for (auto&& e: edges) print(e.frm, e.to, e.cost, e.id); } else { print("indptr", indptr); print("frm to cost id"); FOR(v, N) for (auto&& e: (*this)[v]) print(e.frm, e.to, e.cost, e.id); } } #endif vc new_idx; vc used_e; // G における頂点 V[i] が、新しいグラフで i になるようにする // {G, es} Graph rearrange(vc V, bool keep_eid = 0) { if (len(new_idx) != N) new_idx.assign(N, -1); if (len(used_e) != M) used_e.assign(M, 0); int n = len(V); FOR(i, n) new_idx[V[i]] = i; Graph G(n); vc history; FOR(i, n) { for (auto&& e: (*this)[V[i]]) { if (used_e[e.id]) continue; int a = e.frm, b = e.to; if (new_idx[a] != -1 && new_idx[b] != -1) { history.eb(e.id); used_e[e.id] = 1; int eid = (keep_eid ? e.id : -1); G.add(new_idx[a], new_idx[b], e.cost, eid); } } } FOR(i, n) new_idx[V[i]] = -1; for (auto&& eid: history) used_e[eid] = 0; G.build(); return G; } private: void calc_deg() { assert(vc_deg.empty()); vc_deg.resize(N); for (auto&& e: edges) vc_deg[e.frm]++, vc_deg[e.to]++; } void calc_deg_inout() { assert(vc_indeg.empty()); vc_indeg.resize(N); vc_outdeg.resize(N); for (auto&& e: edges) { vc_indeg[e.to]++, vc_outdeg[e.frm]++; } } }; #line 3 "/home/maspy/compro/library/graph/shortest_path/bfs01.hpp" template pair, vc> bfs01(GT& G, int v) { assert(G.is_prepared()); int N = G.N; vc dist(N, infty); vc par(N, -1); deque que; dist[v] = 0; que.push_front(v); while (!que.empty()) { auto v = que.front(); que.pop_front(); for (auto&& e: G[v]) { if (dist[e.to] == infty || dist[e.to] > dist[e.frm] + e.cost) { dist[e.to] = dist[e.frm] + e.cost; par[e.to] = e.frm; if (e.cost == 0) que.push_front(e.to); else que.push_back(e.to); } } } return {dist, par}; } // 多点スタート。[dist, par, root] template tuple, vc, vc> bfs01(GT& G, vc vs) { assert(G.is_prepared()); int N = G.N; vc dist(N, infty); vc par(N, -1); vc root(N, -1); deque que; for (auto&& v: vs) { dist[v] = 0; root[v] = v; que.push_front(v); } while (!que.empty()) { auto v = que.front(); que.pop_front(); for (auto&& e: G[v]) { if (dist[e.to] == infty || dist[e.to] > dist[e.frm] + e.cost) { dist[e.to] = dist[e.frm] + e.cost; root[e.to] = root[e.frm]; par[e.to] = e.frm; if (e.cost == 0) que.push_front(e.to); else que.push_back(e.to); } } } return {dist, par, root}; } #line 2 "/home/maspy/compro/library/poly/fps_div.hpp" #line 2 "/home/maspy/compro/library/poly/count_terms.hpp" template int count_terms(const vc& f){ int t = 0; FOR(i, len(f)) if(f[i] != mint(0)) ++t; return t; } #line 2 "/home/maspy/compro/library/mod/mod_inv.hpp" // long でも大丈夫 // (val * x - 1) が mod の倍数になるようにする // 特に mod=0 なら x=0 が満たす ll mod_inv(ll val, ll mod) { if (mod == 0) return 0; mod = abs(mod); val %= mod; if (val < 0) val += mod; ll a = val, b = mod, u = 1, v = 0, t; while (b > 0) { t = a / b; swap(a -= t * b, b), swap(u -= t * v, v); } if (u < 0) u += mod; return u; } #line 1 "/home/maspy/compro/library/mod/crt3.hpp" constexpr u32 mod_pow_constexpr(u64 a, u64 n, u32 mod) { a %= mod; u64 res = 1; FOR(32) { if (n & 1) res = res * a % mod; a = a * a % mod, n /= 2; } return res; } template T CRT3(u64 a0, u64 a1, u64 a2) { static_assert(p0 < p1 && p1 < p2); static constexpr u64 x0_1 = mod_pow_constexpr(p0, p1 - 2, p1); static constexpr u64 x01_2 = mod_pow_constexpr(u64(p0) * p1 % p2, p2 - 2, p2); u64 c = (a1 - a0 + p1) * x0_1 % p1; u64 a = a0 + c * p0; c = (a2 - a % p2 + p2) * x01_2 % p2; return T(a) + T(c) * T(p0) * T(p1); } #line 2 "/home/maspy/compro/library/poly/convolution_naive.hpp" template ::value>::type* = nullptr> vc convolution_naive(const vc& a, const vc& b) { int n = int(a.size()), m = int(b.size()); if (n > m) return convolution_naive(b, a); if (n == 0) return {}; vector ans(n + m - 1); FOR(i, n) FOR(j, m) ans[i + j] += a[i] * b[j]; return ans; } template ::value>::type* = nullptr> vc convolution_naive(const vc& a, const vc& b) { int n = int(a.size()), m = int(b.size()); if (n > m) return convolution_naive(b, a); if (n == 0) return {}; vc ans(n + m - 1); if (n <= 16 && (T::get_mod() < (1 << 30))) { for (int k = 0; k < n + m - 1; ++k) { int s = max(0, k - m + 1); int t = min(n, k + 1); u64 sm = 0; for (int i = s; i < t; ++i) { sm += u64(a[i].val) * (b[k - i].val); } ans[k] = sm; } } else { for (int k = 0; k < n + m - 1; ++k) { int s = max(0, k - m + 1); int t = min(n, k + 1); u128 sm = 0; for (int i = s; i < t; ++i) { sm += u64(a[i].val) * (b[k - i].val); } ans[k] = T::raw(sm % T::get_mod()); } } return ans; } #line 2 "/home/maspy/compro/library/poly/convolution_karatsuba.hpp" // 任意の環でできる template vc convolution_karatsuba(const vc& f, const vc& g) { const int thresh = 30; if (min(len(f), len(g)) <= thresh) return convolution_naive(f, g); int n = max(len(f), len(g)); int m = ceil(n, 2); vc f1, f2, g1, g2; if (len(f) < m) f1 = f; if (len(f) >= m) f1 = {f.begin(), f.begin() + m}; if (len(f) >= m) f2 = {f.begin() + m, f.end()}; if (len(g) < m) g1 = g; if (len(g) >= m) g1 = {g.begin(), g.begin() + m}; if (len(g) >= m) g2 = {g.begin() + m, g.end()}; vc a = convolution_karatsuba(f1, g1); vc b = convolution_karatsuba(f2, g2); FOR(i, len(f2)) f1[i] += f2[i]; FOR(i, len(g2)) g1[i] += g2[i]; vc c = convolution_karatsuba(f1, g1); vc F(len(f) + len(g) - 1); assert(2 * m + len(b) <= len(F)); FOR(i, len(a)) F[i] += a[i], c[i] -= a[i]; FOR(i, len(b)) F[2 * m + i] += b[i], c[i] -= b[i]; if (c.back() == T(0)) c.pop_back(); FOR(i, len(c)) if (c[i] != T(0)) F[m + i] += c[i]; return F; } #line 2 "/home/maspy/compro/library/poly/ntt.hpp" template void ntt(vector& a, bool inverse) { assert(mint::can_ntt()); const int rank2 = mint::ntt_info().fi; const int mod = mint::get_mod(); static array root, iroot; static array rate2, irate2; static array rate3, irate3; static bool prepared = 0; if (!prepared) { prepared = 1; root[rank2] = mint::ntt_info().se; iroot[rank2] = mint(1) / root[rank2]; FOR_R(i, rank2) { root[i] = root[i + 1] * root[i + 1]; iroot[i] = iroot[i + 1] * iroot[i + 1]; } mint prod = 1, iprod = 1; for (int i = 0; i <= rank2 - 2; i++) { rate2[i] = root[i + 2] * prod; irate2[i] = iroot[i + 2] * iprod; prod *= iroot[i + 2]; iprod *= root[i + 2]; } prod = 1, iprod = 1; for (int i = 0; i <= rank2 - 3; i++) { rate3[i] = root[i + 3] * prod; irate3[i] = iroot[i + 3] * iprod; prod *= iroot[i + 3]; iprod *= root[i + 3]; } } int n = int(a.size()); int h = topbit(n); assert(n == 1 << h); if (!inverse) { int len = 0; while (len < h) { if (h - len == 1) { int p = 1 << (h - len - 1); mint rot = 1; FOR(s, 1 << len) { int offset = s << (h - len); FOR(i, p) { auto l = a[i + offset]; auto r = a[i + offset + p] * rot; a[i + offset] = l + r; a[i + offset + p] = l - r; } rot *= rate2[topbit(~s & -~s)]; } len++; } else { int p = 1 << (h - len - 2); mint rot = 1, imag = root[2]; for (int s = 0; s < (1 << len); s++) { mint rot2 = rot * rot; mint rot3 = rot2 * rot; int offset = s << (h - len); for (int i = 0; i < p; i++) { u64 mod2 = u64(mod) * mod; u64 a0 = a[i + offset].val; u64 a1 = u64(a[i + offset + p].val) * rot.val; u64 a2 = u64(a[i + offset + 2 * p].val) * rot2.val; u64 a3 = u64(a[i + offset + 3 * p].val) * rot3.val; u64 a1na3imag = (a1 + mod2 - a3) % mod * imag.val; u64 na2 = mod2 - a2; a[i + offset] = a0 + a2 + a1 + a3; a[i + offset + 1 * p] = a0 + a2 + (2 * mod2 - (a1 + a3)); a[i + offset + 2 * p] = a0 + na2 + a1na3imag; a[i + offset + 3 * p] = a0 + na2 + (mod2 - a1na3imag); } rot *= rate3[topbit(~s & -~s)]; } len += 2; } } } else { mint coef = mint(1) / mint(len(a)); FOR(i, len(a)) a[i] *= coef; int len = h; while (len) { if (len == 1) { int p = 1 << (h - len); mint irot = 1; FOR(s, 1 << (len - 1)) { int offset = s << (h - len + 1); FOR(i, p) { u64 l = a[i + offset].val; u64 r = a[i + offset + p].val; a[i + offset] = l + r; a[i + offset + p] = (mod + l - r) * irot.val; } irot *= irate2[topbit(~s & -~s)]; } len--; } else { int p = 1 << (h - len); mint irot = 1, iimag = iroot[2]; FOR(s, (1 << (len - 2))) { mint irot2 = irot * irot; mint irot3 = irot2 * irot; int offset = s << (h - len + 2); for (int i = 0; i < p; i++) { u64 a0 = a[i + offset + 0 * p].val; u64 a1 = a[i + offset + 1 * p].val; u64 a2 = a[i + offset + 2 * p].val; u64 a3 = a[i + offset + 3 * p].val; u64 x = (mod + a2 - a3) * iimag.val % mod; a[i + offset] = a0 + a1 + a2 + a3; a[i + offset + 1 * p] = (a0 + mod - a1 + x) * irot.val; a[i + offset + 2 * p] = (a0 + a1 + 2 * mod - a2 - a3) * irot2.val; a[i + offset + 3 * p] = (a0 + 2 * mod - a1 - x) * irot3.val; } irot *= irate3[topbit(~s & -~s)]; } len -= 2; } } } } #line 1 "/home/maspy/compro/library/poly/fft.hpp" namespace CFFT { using real = double; struct C { real x, y; C() : x(0), y(0) {} C(real x, real y) : x(x), y(y) {} inline C operator+(const C& c) const { return C(x + c.x, y + c.y); } inline C operator-(const C& c) const { return C(x - c.x, y - c.y); } inline C operator*(const C& c) const { return C(x * c.x - y * c.y, x * c.y + y * c.x); } inline C conj() const { return C(x, -y); } }; const real PI = acosl(-1); int base = 1; vector 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; } } } } } // namespace CFFT #line 9 "/home/maspy/compro/library/poly/convolution.hpp" template vector convolution_ntt(vector a, vector b) { if (a.empty() || b.empty()) return {}; int n = int(a.size()), m = int(b.size()); int sz = 1; while (sz < n + m - 1) sz *= 2; // sz = 2^k のときの高速化。分割統治的なやつで損しまくるので。 if ((n + m - 3) <= sz / 2) { auto a_last = a.back(), b_last = b.back(); a.pop_back(), b.pop_back(); auto c = convolution(a, b); c.resize(n + m - 1); c[n + m - 2] = a_last * b_last; FOR(i, len(a)) c[i + len(b)] += a[i] * b_last; FOR(i, len(b)) c[i + len(a)] += b[i] * a_last; return c; } a.resize(sz), b.resize(sz); bool same = a == b; ntt(a, 0); if (same) { b = a; } else { ntt(b, 0); } FOR(i, sz) a[i] *= b[i]; ntt(a, 1); a.resize(n + m - 1); return a; } template vector convolution_garner(const vector& a, const vector& b) { int n = len(a), m = len(b); if (!n || !m) return {}; static constexpr int p0 = 167772161; static constexpr int p1 = 469762049; static constexpr int p2 = 754974721; using mint0 = modint; using mint1 = modint; using mint2 = modint; vc a0(n), b0(m); vc a1(n), b1(m); vc a2(n), b2(m); FOR(i, n) a0[i] = a[i].val, a1[i] = a[i].val, a2[i] = a[i].val; FOR(i, m) b0[i] = b[i].val, b1[i] = b[i].val, b2[i] = b[i].val; auto c0 = convolution_ntt(a0, b0); auto c1 = convolution_ntt(a1, b1); auto c2 = convolution_ntt(a2, b2); vc c(len(c0)); FOR(i, n + m - 1) { c[i] = CRT3(c0[i].val, c1[i].val, c2[i].val); } return c; } template vc convolution_fft(const vc& a, const vc& b) { using C = CFFT::C; int need = (int)a.size() + (int)b.size() - 1; int nbase = 1; while ((1 << nbase) < need) nbase++; CFFT::ensure_base(nbase); int sz = 1 << nbase; vector 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); } CFFT::fft(fa, sz); C r(0, -0.25 / (sz >> 1)), s(0, 1), t(0.5, 0); for (int i = 0; i <= (sz >> 1); i++) { int j = (sz - i) & (sz - 1); C z = (fa[j] * fa[j] - (fa[i] * fa[i]).conj()) * r; fa[j] = (fa[i] * fa[i] - (fa[j] * fa[j]).conj()) * r; fa[i] = z; } for (int i = 0; i < (sz >> 1); i++) { C A0 = (fa[i] + fa[i + (sz >> 1)]) * t; C A1 = (fa[i] - fa[i + (sz >> 1)]) * t * CFFT::rts[(sz >> 1) + i]; fa[i] = A0 + A1 * s; } CFFT::fft(fa, sz >> 1); vector ret(need); for (int i = 0; i < need; i++) { ret[i] = (i & 1 ? fa[i >> 1].y : fa[i >> 1].x); } return ret; } vector convolution(const vector& a, const vector& b) { int n = len(a), m = len(b); if (!n || !m) return {}; if (min(n, m) <= 2500) return convolution_naive(a, b); ll abs_sum_a = 0, abs_sum_b = 0; ll LIM = 1e15; FOR(i, n) abs_sum_a = min(LIM, abs_sum_a + abs(a[i])); FOR(i, m) abs_sum_b = min(LIM, abs_sum_b + abs(b[i])); if (i128(abs_sum_a) * abs_sum_b < 1e15) { vc c = convolution_fft(a, b); vc res(len(c)); FOR(i, len(c)) res[i] = ll(floor(c[i] + .5)); return res; } static constexpr unsigned long long MOD1 = 754974721; // 2^24 static constexpr unsigned long long MOD2 = 167772161; // 2^25 static constexpr unsigned long long MOD3 = 469762049; // 2^26 static constexpr unsigned long long M2M3 = MOD2 * MOD3; static constexpr unsigned long long M1M3 = MOD1 * MOD3; static constexpr unsigned long long M1M2 = MOD1 * MOD2; static constexpr unsigned long long M1M2M3 = MOD1 * MOD2 * MOD3; static const unsigned long long i1 = mod_inv(MOD2 * MOD3, MOD1); static const unsigned long long i2 = mod_inv(MOD1 * MOD3, MOD2); static const unsigned long long i3 = mod_inv(MOD1 * MOD2, MOD3); using mint1 = modint; using mint2 = modint; using mint3 = modint; vc a1(n), b1(m); vc a2(n), b2(m); vc a3(n), b3(m); FOR(i, n) a1[i] = a[i], a2[i] = a[i], a3[i] = a[i]; FOR(i, m) b1[i] = b[i], b2[i] = b[i], b3[i] = b[i]; auto c1 = convolution_ntt(a1, b1); auto c2 = convolution_ntt(a2, b2); auto c3 = convolution_ntt(a3, b3); vc c(n + m - 1); FOR(i, n + m - 1) { u64 x = 0; x += (c1[i].val * i1) % MOD1 * M2M3; x += (c2[i].val * i2) % MOD2 * M1M3; x += (c3[i].val * i3) % MOD3 * M1M2; ll diff = c1[i].val - ((long long)(x) % (long long)(MOD1)); if (diff < 0) diff += MOD1; static constexpr unsigned long long offset[5] = {0, 0, M1M2M3, 2 * M1M2M3, 3 * M1M2M3}; x -= offset[diff % 5]; c[i] = x; } return c; } template vc convolution(const vc& a, const vc& b) { int n = len(a), m = len(b); if (!n || !m) return {}; if (mint::can_ntt()) { if (min(n, m) <= 50) return convolution_karatsuba(a, b); return convolution_ntt(a, b); } if (min(n, m) <= 200) return convolution_karatsuba(a, b); return convolution_garner(a, b); } #line 4 "/home/maspy/compro/library/poly/fps_inv.hpp" template vc fps_inv_sparse(const vc& f) { int N = len(f); vc> dat; FOR(i, 1, N) if (f[i] != mint(0)) dat.eb(i, f[i]); vc g(N); mint g0 = mint(1) / f[0]; g[0] = g0; FOR(n, 1, N) { mint rhs = 0; for (auto&& [k, fk]: dat) { if (k > n) break; rhs -= fk * g[n - k]; } g[n] = rhs * g0; } return g; } template vc fps_inv_dense_ntt(const vc& F) { vc G = {mint(1) / F[0]}; ll N = len(F), n = 1; G.reserve(N); while (n < N) { vc f(2 * n), g(2 * n); FOR(i, min(N, 2 * n)) f[i] = F[i]; FOR(i, n) g[i] = G[i]; ntt(f, false), ntt(g, false); FOR(i, 2 * n) f[i] *= g[i]; ntt(f, true); FOR(i, n) f[i] = 0; ntt(f, false); FOR(i, 2 * n) f[i] *= g[i]; ntt(f, true); FOR(i, n, min(N, 2 * n)) G.eb(-f[i]); n *= 2; } return G; } template vc fps_inv_dense(const vc& F) { if (mint::can_ntt()) return fps_inv_dense_ntt(F); const int N = len(F); vc R = {mint(1) / F[0]}; vc p; int m = 1; while (m < N) { p = convolution(R, R); p.resize(m + m); vc f = {F.begin(), F.begin() + min(m + m, N)}; p = convolution(p, f); R.resize(m + m); FOR(i, m + m) R[i] = R[i] + R[i] - p[i]; m += m; } R.resize(N); return R; } template vc fps_inv(const vc& f) { assert(f[0] != mint(0)); int n = count_terms(f); int t = (mint::can_ntt() ? 160 : 820); return (n <= t ? fps_inv_sparse(f) : fps_inv_dense(f)); } #line 5 "/home/maspy/compro/library/poly/fps_div.hpp" // f/g. f の長さで出力される. template vc fps_div(vc f, vc g) { if (SPARSE || count_terms(g) < 200) return fps_div_sparse(f, g); int n = len(f); g.resize(n); g = fps_inv(g); f = convolution(f, g); f.resize(n); return f; } // f/g ただし g は sparse template vc fps_div_sparse(vc f, vc& g) { if (g[0] != mint(1)) { mint cf = g[0].inverse(); for (auto&& x: f) x *= cf; for (auto&& x: g) x *= cf; } vc> dat; FOR(i, 1, len(g)) if (g[i] != mint(0)) dat.eb(i, -g[i]); FOR(i, len(f)) { for (auto&& [j, x]: dat) { if (i >= j) f[i] += x * f[i - j]; } } return f; } #line 2 "/home/maspy/compro/library/poly/ntt_doubling.hpp" template void ntt_doubling(vector& a) { const int rank2 = mint::ntt_info().fi; static array root; static bool prepared = 0; if (!prepared) { prepared = 1; root[rank2] = mint::ntt_info().se; FOR_R(i, rank2) { root[i] = root[i + 1] * root[i + 1]; } } const int M = (int)a.size(); auto b = a; ntt(b, 1); mint r = 1, zeta = root[topbit(2 * M)]; FOR(i, M) b[i] *= r, r *= zeta; ntt(b, 0); copy(begin(b), end(b), back_inserter(a)); } #line 3 "/home/maspy/compro/library/poly/coef_of_rational_fps.hpp" template mint coef_of_rational_fps_small(vector P, vector Q, ll N) { assert(len(Q) <= 16); int m = len(Q) - 1; assert(len(P) == m); if (m == 0) return mint(0); vc Q32(m + 1); FOR(i, m + 1) Q32[i] = (-Q[i]).val; using poly = vc; auto dfs = [&](auto& dfs, const ll N) -> poly { // x^N mod G if (N == 0) return {1}; poly f = dfs(dfs, N / 2); poly g(len(f) * 2 - 1 + (N & 1)); FOR(i, len(f)) FOR(j, len(f)) { g[i + j + (N & 1)] += f[i] * f[j]; } FOR(i, len(g)) g[i] = mint(g[i]).val; FOR_R(i, len(g)) { g[i] = mint(g[i]).val; if (i >= m) FOR(j, 1, len(Q)) g[i - j] += Q32[j] * g[i]; } g.resize(m); return g; }; poly f = dfs(dfs, N); FOR(i, m) { FOR(j, 1, i + 1) P[i] -= Q[j] * P[i - j]; } u64 res = 0; FOR(i, m) res += f[i] * P[i].val; return res; } template mint coef_of_rational_fps_ntt(vector P, vector Q, ll N) { int log = 0; while ((1 << log) < len(Q)) ++log; int n = 1 << log; P.resize(2 * n), Q.resize(2 * n); ntt(P, 0), ntt(Q, 0); vc btr(n); FOR(i, n) { btr[i] = (btr[i >> 1] >> 1) + ((i & 1) << (log - 1)); } int t = mint::ntt_info().fi; mint r = mint::ntt_info().se; mint dw = r.inverse().pow((1 << t) / (2 * n)); vc S, T; while (N >= n) { mint w = inv(2); T.resize(n); FOR(i, n) T[i] = Q[2 * i + 0] * Q[2 * i + 1]; S.resize(n); if (N & 1) { for (auto& i: btr) { S[i] = (P[2 * i] * Q[2 * i + 1] - P[2 * i + 1] * Q[2 * i]) * w; w *= dw; } } else { FOR(i, n) { S[i] = (P[2 * i] * Q[2 * i + 1] + P[2 * i + 1] * Q[2 * i]) * w; } } swap(P, S), swap(Q, T); N >>= 1; if (N < n) break; ntt_doubling(P); ntt_doubling(Q); } ntt(P, 1), ntt(Q, 1); return fps_div(P, Q)[N]; } template mint coef_of_rational_fps_convolution(vector P, vector Q, ll N) { P.resize(len(Q) - 1); if (len(P) == 0) return 0; while (N >= len(P)) { vc Q1 = Q; FOR(i, len(Q1)) if (i & 1) Q1[i] = -Q1[i]; P = convolution(P, Q1); Q = convolution(Q, Q1); FOR(i, len(Q1)) Q[i] = Q[2 * i]; FOR(i, len(Q1) - 1) P[i] = P[2 * i | (N & 1)]; P.resize(len(Q1) - 1); Q.resize(len(Q1)); N /= 2; } return fps_div(P, Q)[N]; } template mint coef_of_rational_fps(vector P, vector Q, ll N) { assert(len(P) < len(Q) && Q[0] == mint(1)); if (N == 0) return (P.empty() ? mint(0) : P[0]); int n = len(Q); if (mint::ntt_info().fi != -1) { if (n <= 10) { return coef_of_rational_fps_small(P, Q, N); } else { return coef_of_rational_fps_ntt(P, Q, N); } } return (n <= 16 ? coef_of_rational_fps_small(P, Q, N) : coef_of_rational_fps_convolution(P, Q, N)); } #line 2 "/home/maspy/compro/library/poly/poly_taylor_shift.hpp" #line 2 "/home/maspy/compro/library/nt/primetable.hpp" template vc primetable(int LIM) { ++LIM; const int S = 32768; static int done = 2; static vc primes = {2}, sieve(S + 1); if (done < LIM) { done = LIM; primes = {2}, sieve.assign(S + 1, 0); const int R = LIM / 2; primes.reserve(int(LIM / log(LIM) * 1.1)); vc> cp; for (int i = 3; i <= S; i += 2) { if (!sieve[i]) { cp.eb(i, i * i / 2); for (int j = i * i; j <= S; j += 2 * i) sieve[j] = 1; } } for (int L = 1; L <= R; L += S) { array block{}; for (auto& [p, idx]: cp) for (int i = idx; i < S + L; idx = (i += p)) block[i - L] = 1; FOR(i, min(S, R - L)) if (!block[i]) primes.eb((L + i) * 2 + 1); } } int k = LB(primes, LIM + 1); return {primes.begin(), primes.begin() + k}; } #line 3 "/home/maspy/compro/library/mod/powertable.hpp" // a^0, ..., a^N template vc powertable_1(mint a, ll N) { // table of a^i vc f(N + 1, 1); FOR(i, N) f[i + 1] = a * f[i]; return f; } // 0^e, ..., N^e template vc powertable_2(ll e, ll N) { auto primes = primetable(N); vc f(N + 1, 1); f[0] = mint(0).pow(e); for (auto&& p: primes) { if (p > N) break; mint xp = mint(p).pow(e); ll pp = p; while (pp <= N) { ll i = pp; while (i <= N) { f[i] *= xp; i += pp; } pp *= p; } } return f; } #line 5 "/home/maspy/compro/library/poly/poly_taylor_shift.hpp" // f(x) -> f(x+c) template vc poly_taylor_shift(vc f, mint c) { ll N = len(f); FOR(i, N) f[i] *= fact(i); auto b = powertable_1(c, N); FOR(i, N) b[i] *= fact_inv(i); reverse(all(f)); f = convolution(f, b); f.resize(N); reverse(all(f)); FOR(i, N) f[i] *= fact_inv(i); return f; } #line 2 "/home/maspy/compro/library/ds/unionfind/unionfind.hpp" struct UnionFind { int n, n_comp; vc dat; // par or (-size) UnionFind(int n = 0) { build(n); } void build(int m) { n = m, n_comp = m; dat.assign(n, -1); } void reset() { build(n); } int operator[](int x) { while (dat[x] >= 0) { int pp = dat[dat[x]]; if (pp < 0) { return dat[x]; } x = dat[x] = pp; } return x; } ll size(int x) { x = (*this)[x]; return -dat[x]; } bool merge(int x, int y) { x = (*this)[x], y = (*this)[y]; if (x == y) return false; if (-dat[x] < -dat[y]) swap(x, y); dat[x] += dat[y], dat[y] = x, n_comp--; return true; } }; #line 2 "/home/maspy/compro/library/poly/convolution_all.hpp" #line 4 "/home/maspy/compro/library/poly/convolution_all.hpp" template vc convolution_all(vc>& polys) { if (len(polys) == 0) return {T(1)}; while (1) { int n = len(polys); if (n == 1) break; int m = ceil(n, 2); FOR(i, m) { if (2 * i + 1 == n) { polys[i] = polys[2 * i]; } else { polys[i] = convolution(polys[2 * i], polys[2 * i + 1]); } } polys.resize(m); } return polys[0]; } #line 2 "/home/maspy/compro/library/graph/tree.hpp" #line 4 "/home/maspy/compro/library/graph/tree.hpp" // HLD euler tour をとっていろいろ。 template struct Tree { using Graph_type = GT; GT &G; using WT = typename GT::cost_type; int N; vector LID, RID, head, V, parent, VtoE; vc depth; vc depth_weighted; Tree(GT &G, int r = 0, bool hld = 1) : G(G) { build(r, hld); } void build(int r = 0, bool hld = 1) { if (r == -1) return; // build を遅延したいとき N = G.N; LID.assign(N, -1), RID.assign(N, -1), head.assign(N, r); V.assign(N, -1), parent.assign(N, -1), VtoE.assign(N, -1); depth.assign(N, -1), depth_weighted.assign(N, 0); assert(G.is_prepared()); int t1 = 0; dfs_sz(r, -1, hld); dfs_hld(r, t1); } void dfs_sz(int v, int p, bool hld) { auto &sz = RID; parent[v] = p; depth[v] = (p == -1 ? 0 : depth[p] + 1); sz[v] = 1; int l = G.indptr[v], r = G.indptr[v + 1]; auto &csr = G.csr_edges; // 使う辺があれば先頭にする for (int i = r - 2; i >= l; --i) { if (hld && depth[csr[i + 1].to] == -1) swap(csr[i], csr[i + 1]); } int hld_sz = 0; for (int i = l; i < r; ++i) { auto e = csr[i]; if (depth[e.to] != -1) continue; depth_weighted[e.to] = depth_weighted[v] + e.cost; VtoE[e.to] = e.id; dfs_sz(e.to, v, hld); sz[v] += sz[e.to]; if (hld && chmax(hld_sz, sz[e.to]) && l < i) { swap(csr[l], csr[i]); } } } void dfs_hld(int v, int ×) { LID[v] = times++; RID[v] += LID[v]; V[LID[v]] = v; bool heavy = true; for (auto &&e: G[v]) { if (depth[e.to] <= depth[v]) continue; head[e.to] = (heavy ? head[v] : e.to); heavy = false; dfs_hld(e.to, times); } } vc heavy_path_at(int v) { vc P = {v}; while (1) { int a = P.back(); for (auto &&e: G[a]) { if (e.to != parent[a] && head[e.to] == v) { P.eb(e.to); break; } } if (P.back() == a) break; } return P; } int heavy_child(int v) { int k = LID[v] + 1; if (k == N) return -1; int w = V[k]; return (parent[w] == v ? w : -1); } int e_to_v(int eid) { auto e = G.edges[eid]; return (parent[e.frm] == e.to ? e.frm : e.to); } int v_to_e(int v) { return VtoE[v]; } int ELID(int v) { return 2 * LID[v] - depth[v]; } int ERID(int v) { return 2 * RID[v] - depth[v] - 1; } // 目標地点へ進む個数が k int LA(int v, int k) { assert(k <= depth[v]); while (1) { int u = head[v]; if (LID[v] - k >= LID[u]) return V[LID[v] - k]; k -= LID[v] - LID[u] + 1; v = parent[u]; } } int la(int u, int v) { return LA(u, v); } int LCA(int u, int v) { for (;; v = parent[head[v]]) { if (LID[u] > LID[v]) swap(u, v); if (head[u] == head[v]) return u; } } // root を根とした場合の lca int LCA_root(int u, int v, int root) { return LCA(u, v) ^ LCA(u, root) ^ LCA(v, root); } int lca(int u, int v) { return LCA(u, v); } int lca_root(int u, int v, int root) { return LCA_root(u, v, root); } int subtree_size(int v, int root = -1) { if (root == -1) return RID[v] - LID[v]; if (v == root) return N; int x = jump(v, root, 1); if (in_subtree(v, x)) return RID[v] - LID[v]; return N - RID[x] + LID[x]; } int dist(int a, int b) { int c = LCA(a, b); return depth[a] + depth[b] - 2 * depth[c]; } WT dist_weighted(int a, int b) { int c = LCA(a, b); return depth_weighted[a] + depth_weighted[b] - WT(2) * depth_weighted[c]; } // a is in b bool in_subtree(int a, int b) { return LID[b] <= LID[a] && LID[a] < RID[b]; } int jump(int a, int b, ll k) { if (k == 1) { if (a == b) return -1; return (in_subtree(b, a) ? LA(b, depth[b] - depth[a] - 1) : parent[a]); } int c = LCA(a, b); int d_ac = depth[a] - depth[c]; int d_bc = depth[b] - depth[c]; if (k > d_ac + d_bc) return -1; if (k <= d_ac) return LA(a, k); return LA(b, d_ac + d_bc - k); } vc collect_child(int v) { vc res; for (auto &&e: G[v]) if (e.to != parent[v]) res.eb(e.to); return res; } vc collect_light(int v) { vc res; bool skip = true; for (auto &&e: G[v]) if (e.to != parent[v]) { if (!skip) res.eb(e.to); skip = false; } return res; } vc> get_path_decomposition(int u, int v, bool edge) { // [始点, 終点] の"閉"区間列。 vc> up, down; while (1) { if (head[u] == head[v]) break; if (LID[u] < LID[v]) { down.eb(LID[head[v]], LID[v]); v = parent[head[v]]; } else { up.eb(LID[u], LID[head[u]]); u = parent[head[u]]; } } if (LID[u] < LID[v]) down.eb(LID[u] + edge, LID[v]); elif (LID[v] + edge <= LID[u]) up.eb(LID[u], LID[v] + edge); reverse(all(down)); up.insert(up.end(), all(down)); return up; } vc restore_path(int u, int v) { vc P; for (auto &&[a, b]: get_path_decomposition(u, v, 0)) { if (a <= b) { FOR(i, a, b + 1) P.eb(V[i]); } else { FOR_R(i, b, a + 1) P.eb(V[i]); } } return P; } }; #line 2 "/home/maspy/compro/library/graph/ds/static_toptree.hpp" /* tute さんの実装 https://yukicoder.me/submissions/838092 を参考にしている. いわゆる toptree (辺からはじめてマージ過程を木にする)とは少し異なるはず. 木を「heavy path 上の辺で分割」「根を virtual にする」 「light edges の分割」「light edge を消す」で頂点に分割していく. 逆にたどれば,1 頂点からはじめて木全体を作る高さ O(logN) の木になる. 高さについて:https://www.mathenachia.blog/mergetech-and-logn/ ・lch == rch == -1:頂点 ・rch == -1: ・heavy なら light の集約に頂点を付加したもの ・light なら 根付き木に light edge を付加したもの ・子が 2 つ ・heavy なら heavy path を辺で結合したもの ・light なら light edge たちのマージ */ template struct Static_TopTree { TREE &tree; vc par, lch, rch, A, B; vc heavy; Static_TopTree(TREE &tree) : tree(tree) { int root = tree.V[0]; build(root); // relabel int n = len(par); reverse(all(par)), reverse(all(lch)), reverse(all(rch)), reverse(all(A)), reverse(all(B)), reverse(all(heavy)); for (auto &x: par) x = (x == -1 ? -1 : n - 1 - x); for (auto &x: lch) x = (x == -1 ? -1 : n - 1 - x); for (auto &x: rch) x = (x == -1 ? -1 : n - 1 - x); } // 木全体での集約値を得る // from_vertex(v) // add_vertex(x, v) // add_edge(x, u, v) : u が親 // merge_light(x, y) // merge_heavy(x, y, a, b, c, d) : [a,b] + [c,d] = [a,d] template Data tree_dp(F1 from_vertex, F2 add_vertex, F3 add_edge, F4 merge_light, F5 merge_heavy) { auto dfs = [&](auto &dfs, int k) -> Data { if (lch[k] == -1 && rch[k] == -1) { return from_vertex(A[k]); } if (rch[k] == -1) { Data x = dfs(dfs, lch[k]); if (heavy[k]) { return add_vertex(x, A[k]); } else { return add_edge(x, A[k], B[lch[k]]); } } Data x = dfs(dfs, lch[k]); Data y = dfs(dfs, rch[k]); if (heavy[k]) { return merge_heavy(x, y, A[lch[k]], B[lch[k]], A[rch[k]], B[rch[k]]); } return merge_light(x, y); }; return dfs(dfs, 0); } private: int add_node(int l, int r, int a, int b, bool h) { int ret = len(par); par.eb(-1), lch.eb(l), rch.eb(r), A.eb(a), B.eb(b), heavy.eb(h); if (l != -1) par[l] = ret; if (r != -1) par[r] = ret; return ret; } int build(int v) { // v は heavy path の根なので v を根とする部分木に対応するノードを作る assert(tree.head[v] == v); auto path = tree.heavy_path_at(v); reverse(all(path)); auto dfs = [&](auto &dfs, int l, int r) -> int { // path[l:r) if (l + 1 < r) { int m = (l + r) / 2; int x = dfs(dfs, l, m); int y = dfs(dfs, m, r); return add_node(x, y, path[l], path[r - 1], true); } assert(r == l + 1); int me = path[l]; // sz, idx pqg> que; for (auto &to: tree.collect_light(me)) { int x = build(to); int y = add_node(x, -1, me, me, false); que.emplace(tree.subtree_size(to), y); } if (que.empty()) { return add_node(-1, -1, me, me, true); } while (len(que) >= 2) { auto [s1, x] = POP(que); auto [s2, y] = POP(que); int z = add_node(x, y, me, me, false); que.emplace(s1 + s2, z); } auto [s, x] = POP(que); return add_node(x, -1, me, me, true); }; return dfs(dfs, 0, len(path)); } }; #line 12 "main.cpp" using mint = modint998; using poly = vc; /* とりあえず stay しないとして解くことを考える A を隣接行列とすると, walk の母関数は 分子:det(I-xA) の cofactor 分母:det(I-xA) 分母について 対角以外をマッチングでとるしかないのでマッチングの数え上げでできる 1-a1x^2+a2x^4-... 分子について (v,u) パスとマッチングに分解する. uv パスの頂点数を m として、uv パスを使わないマッチングの数え上げをする x^m(1-a_1x^2+a_2x^4-...) */ poly count_matching(Graph G) { Tree tree(G); Static_TopTree STT(tree); using Data = array, 2>; auto add = [&](Data& X, int i, int j, int k, mint x) -> void { if (x == mint(0)) return; if (len(X[i][j]) <= k) X[i][j].resize(k + 1); X[i][j][k] += x; }; auto from_vertex = [&](int v) -> Data { Data X; X[0][0] = poly{mint(1)}; return X; }; auto add_vertex = [&](Data& X, int v) -> Data { return X; }; auto add_edge = [&](Data& X, int u, int v) -> Data { Data Y; FOR(a, 2) { FOR(i, len(X[a][0])) { add(Y, 0, 0, i, X[a][0][i]); add(Y, 1, 1, i + 1, X[a][0][i]); } FOR(i, len(X[a][1])) { add(Y, 0, 0, i, X[a][1][i]); } } return Y; }; auto merge_light = [&](Data& X, Data& Y) -> Data { poly &X0 = X[0][0], &X1 = X[1][1]; poly &Y0 = Y[0][0], &Y1 = Y[1][1]; poly A = convolution(X0, Y0); poly B = convolution(X0, Y1); poly C = convolution(X1, Y0); Data Z; FOR(i, len(A)) add(Z, 0, 0, i, A[i]); FOR(i, len(B)) add(Z, 1, 1, i, B[i]); FOR(i, len(C)) add(Z, 1, 1, i, C[i]); return Z; }; auto merge_heavy = [&](Data& X, Data& Y, int va, int vb, int vc, int vd) -> Data { Data Z; FOR_R(a, 2) FOR_R(d, 2) { // 辺を使わない poly f0 = X[a][0], f1 = X[a][1]; poly g0 = Y[0][d], g1 = Y[1][d]; if (len(f0) < len(f1)) swap(f0, f1); if (len(g0) < len(g1)) swap(g0, g1); FOR(i, len(f1)) f0[i] += f1[i]; FOR(i, len(g1)) g0[i] += g1[i]; Z[a][d] = convolution(f0, g0); // 辺を使う poly f = convolution(X[a][0], Y[0][d]); int x = (va != vb ? a : 1); int y = (vc != vd ? d : 1); FOR(i, len(f)) add(Z, x, y, 1 + i, f[i]); } return Z; }; Data X = STT.tree_dp(from_vertex, add_vertex, add_edge, merge_light, merge_heavy); vc ANS; FOR(a, 2) FOR(b, 2) { if (len(ANS) < len(X[a][b])) ANS.resize(len(X[a][b])); FOR(i, len(X[a][b])) { ANS[i] += X[a][b][i]; } } return ANS; } void solve() { LL(N, M, S, T); --S, --T; Graph G(N); G.read_tree(); vc on_path(N); { auto [dist, par] = bfs01(G, S); on_path[T] = 1; while (T != S) { T = par[T]; on_path[T] = 1; } } auto A = count_matching(G); vvc polys; UnionFind uf(N); for (auto& e: G.edges) { if (on_path[e.frm] || on_path[e.to]) continue; uf.merge(e.frm, e.to); } vvc comp(N); FOR(v, N) comp[uf[v]].eb(v); FOR(r, N) { if (on_path[r]) continue; if (uf[r] != r) continue; vc V = comp[r]; if (len(V) == 1) continue; Graph H = G.rearrange(V); poly f = count_matching(H); polys.eb(f); } poly B = convolution_all(polys); // print("A", A); // print("B", B); // ここから先はとりあえず正しい計算量になっているはず poly f(N + 1), g(N + 1); FOR(i, len(A)) { if (A[i] != mint(0)) f[2 * i] += (i % 2 == 0 ? A[i] : -A[i]); } int d = SUM(on_path) - 1; FOR(i, len(B)) { if (B[i] != mint(0)) g[d + 2 * i] += (i % 2 == 0 ? B[i] : -B[i]); } // W(x) = g(x)/f(x) // ANS = sum_m binom(M,m)[x^m]W(x) // EGF(W) = sum_m W_m 1/m! x^m // [x^M]e^x EGF(W) // 根が全部 -1 される // ANS も C-rec で、f(x-1) vc W = fps_div(g, f); FOR(m, N + 1) W[m] *= fact_inv(m); vc tmp(N + 1); FOR(m, N + 1) tmp[m] = fact_inv(m); vc F = convolution(W, tmp); F.resize(N + 1); FOR(i, N + 1) F[i] *= fact(i); reverse(all(f)); f = poly_taylor_shift(f, -1); reverse(all(f)); g = convolution(F, f); g.resize(N); mint ANS = coef_of_rational_fps(g, f, M); print(ANS); } signed main() { int T = 1; // INT(T); FOR(T) solve(); return 0; }