結果
問題 | No.2587 Random Walk on Tree |
ユーザー | maspy |
提出日時 | 2023-12-15 17:58:51 |
言語 | C++23 (gcc 12.3.0 + boost 1.83.0) |
結果 |
AC
|
実行時間 | 1,781 ms / 10,000 ms |
コード長 | 64,139 bytes |
コンパイル時間 | 12,633 ms |
コンパイル使用メモリ | 399,668 KB |
実行使用メモリ | 35,532 KB |
最終ジャッジ日時 | 2024-09-27 13:15:23 |
合計ジャッジ時間 | 43,222 ms |
ジャッジサーバーID (参考情報) |
judge4 / judge2 |
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テストケース
テストケース表示入力 | 結果 | 実行時間 実行使用メモリ |
---|---|---|
testcase_00 | AC | 2 ms
6,812 KB |
testcase_01 | AC | 2 ms
6,812 KB |
testcase_02 | AC | 2 ms
6,812 KB |
testcase_03 | AC | 2 ms
6,940 KB |
testcase_04 | AC | 2 ms
6,940 KB |
testcase_05 | AC | 3 ms
6,940 KB |
testcase_06 | AC | 3 ms
6,940 KB |
testcase_07 | AC | 2 ms
6,940 KB |
testcase_08 | AC | 3 ms
6,944 KB |
testcase_09 | AC | 2 ms
6,944 KB |
testcase_10 | AC | 2 ms
6,940 KB |
testcase_11 | AC | 4 ms
6,940 KB |
testcase_12 | AC | 17 ms
6,940 KB |
testcase_13 | AC | 27 ms
6,944 KB |
testcase_14 | AC | 9 ms
6,940 KB |
testcase_15 | AC | 1,295 ms
26,284 KB |
testcase_16 | AC | 704 ms
16,324 KB |
testcase_17 | AC | 772 ms
18,576 KB |
testcase_18 | AC | 118 ms
6,940 KB |
testcase_19 | AC | 1,445 ms
31,728 KB |
testcase_20 | AC | 1,105 ms
26,200 KB |
testcase_21 | AC | 1,529 ms
29,524 KB |
testcase_22 | AC | 1,412 ms
35,532 KB |
testcase_23 | AC | 1,370 ms
32,044 KB |
testcase_24 | AC | 1,296 ms
26,624 KB |
testcase_25 | AC | 560 ms
27,236 KB |
testcase_26 | AC | 1,781 ms
31,436 KB |
testcase_27 | AC | 1,502 ms
29,384 KB |
testcase_28 | AC | 1,570 ms
26,408 KB |
testcase_29 | AC | 1,594 ms
26,628 KB |
testcase_30 | AC | 1,339 ms
26,428 KB |
testcase_31 | AC | 1,340 ms
27,372 KB |
testcase_32 | AC | 1,725 ms
30,828 KB |
testcase_33 | AC | 2 ms
6,944 KB |
testcase_34 | AC | 885 ms
31,012 KB |
testcase_35 | AC | 887 ms
33,036 KB |
testcase_36 | AC | 874 ms
31,980 KB |
testcase_37 | AC | 872 ms
32,176 KB |
testcase_38 | AC | 1,438 ms
30,580 KB |
testcase_39 | AC | 1,440 ms
30,648 KB |
ソースコード
#line 1 "main.cpp" #define PROBLEM "https://yukicoder.me/problems/no/2587" #line 1 "/home/maspy/compro/library/my_template.hpp" #if defined(LOCAL) #include <my_template_compiled.hpp> #else #pragma GCC optimize("Ofast") #pragma GCC optimize("unroll-loops") #include <bits/stdc++.h> 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 <class T> constexpr T infty = 0; template <> constexpr int infty<int> = 1'000'000'000; template <> constexpr ll infty<ll> = ll(infty<int>) * infty<int> * 2; template <> constexpr u32 infty<u32> = infty<int>; template <> constexpr u64 infty<u64> = infty<ll>; template <> constexpr i128 infty<i128> = i128(infty<ll>) * infty<ll>; template <> constexpr double infty<double> = infty<ll>; template <> constexpr long double infty<long double> = infty<ll>; using pi = pair<ll, ll>; using vi = vector<ll>; template <class T> using vc = vector<T>; template <class T> using vvc = vector<vc<T>>; template <class T> using vvvc = vector<vvc<T>>; template <class T> using vvvvc = vector<vvvc<T>>; template <class T> using vvvvvc = vector<vvvvc<T>>; template <class T> using pq = priority_queue<T>; template <class T> using pqg = priority_queue<T, vector<T>, greater<T>>; #define vv(type, name, h, ...) \ vector<vector<type>> name(h, vector<type>(__VA_ARGS__)) #define vvv(type, name, h, w, ...) \ vector<vector<vector<type>>> name( \ h, vector<vector<type>>(w, vector<type>(__VA_ARGS__))) #define vvvv(type, name, a, b, c, ...) \ vector<vector<vector<vector<type>>>> name( \ a, vector<vector<vector<type>>>( \ b, vector<vector<type>>(c, vector<type>(__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 <typename T> T floor(T a, T b) { return a / b - (a % b && (a ^ b) < 0); } template <typename T> T ceil(T x, T y) { return floor(x + y - 1, y); } template <typename T> T bmod(T x, T y) { return x - y * floor(x, y); } template <typename T> pair<T, T> divmod(T x, T y) { T q = floor(x, y); return {q, x - q * y}; } template <typename T, typename U> T SUM(const vector<U> &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 <typename T> T POP(deque<T> &que) { T a = que.front(); que.pop_front(); return a; } template <typename T> T POP(pq<T> &que) { T a = que.top(); que.pop(); return a; } template <typename T> T POP(pqg<T> &que) { T a = que.top(); que.pop(); return a; } template <typename T> T POP(vc<T> &que) { T a = que.back(); que.pop_back(); return a; } template <typename F> 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 <typename F> 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 <class T, class S> inline bool chmax(T &a, const S &b) { return (a < b ? a = b, 1 : 0); } template <class T, class S> inline bool chmin(T &a, const S &b) { return (a > b ? a = b, 1 : 0); } // ? は -1 vc<int> s_to_vi(const string &S, char first_char) { vc<int> A(S.size()); FOR(i, S.size()) { A[i] = (S[i] != '?' ? S[i] - first_char : -1); } return A; } template <typename T, typename U> vector<T> cumsum(vector<U> &A, int off = 1) { int N = A.size(); vector<T> 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 <typename T> vector<int> argsort(const vector<T> &A) { vector<int> 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 <typename T> vc<T> rearrange(const vc<T> &A, const vc<int> &I) { vc<T> 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 <unistd.h> // 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 <typename T> void rd_real(T &x) { string s; rd(s); x = stod(s); } template <typename T> 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<T>::value || is_same_v<T, i128>) { if (c == '-') { minus = 1, c = ibuf[pil++]; } } x = 0; while ('0' <= c) { x = x * 10 + (c & 15), c = ibuf[pil++]; } if constexpr (is_signed<T>::value || is_same_v<T, i128>) { 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 <class T, class U> void rd(pair<T, U> &p) { return rd(p.first), rd(p.second); } template <size_t N = 0, typename T> void rd_tuple(T &t) { if constexpr (N < std::tuple_size<T>::value) { auto &x = std::get<N>(t); rd(x); rd_tuple<N + 1>(t); } } template <class... T> void rd(tuple<T...> &tpl) { rd_tuple(tpl); } template <size_t N = 0, typename T> void rd(array<T, N> &x) { for (auto &d: x) rd(d); } template <class T> void rd(vc<T> &x) { for (auto &d: x) rd(d); } void read() {} template <class H, class... T> 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 <typename T> 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 <typename T> 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 <class T, class U> void wt(const pair<T, U> val) { wt(val.first); wt(' '); wt(val.second); } template <size_t N = 0, typename T> void wt_tuple(const T t) { if constexpr (N < std::tuple_size<T>::value) { if constexpr (N > 0) { wt(' '); } const auto x = std::get<N>(t); wt(x); wt_tuple<N + 1>(t); } } template <class... T> void wt(tuple<T...> tpl) { wt_tuple(tpl); } template <class T, size_t S> void wt(const array<T, S> val) { auto n = val.size(); for (size_t i = 0; i < n; i++) { if (i) wt(' '); wt(val[i]); } } template <class T> void wt(const vector<T> val) { auto n = val.size(); for (size_t i = 0; i < n; i++) { if (i) wt(' '); wt(val[i]); } } void print() { wt('\n'); } template <class Head, class... Tail> void print(Head &&head, Tail &&... tail) { wt(head); if (sizeof...(Tail)) wt(' '); print(forward<Tail>(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<type> name(size); \ read(name) #define VV(type, name, h, w) \ vector<vector<type>> name(h, vector<type>(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 4 "main.cpp" #line 2 "/home/maspy/compro/library/mod/modint_common.hpp" struct has_mod_impl { template <class T> static auto check(T &&x) -> decltype(x.get_mod(), std::true_type{}); template <class T> static auto check(...) -> std::false_type; }; template <class T> class has_mod : public decltype(has_mod_impl::check<T>(std::declval<T>())) {}; template <typename mint> mint inv(int n) { static const int mod = mint::get_mod(); static vector<mint> dat = {0, 1}; assert(0 <= n); if (n >= mod) n %= mod; while (len(dat) <= n) { int k = len(dat); int q = (mod + k - 1) / k; dat.eb(dat[k * q - mod] * mint::raw(q)); } return dat[n]; } template <typename mint> mint fact(int n) { static const int mod = mint::get_mod(); assert(0 <= n && n < mod); static vector<mint> dat = {1, 1}; while (len(dat) <= n) dat.eb(dat[len(dat) - 1] * mint::raw(len(dat))); return dat[n]; } template <typename mint> mint fact_inv(int n) { static vector<mint> dat = {1, 1}; if (n < 0) return mint(0); while (len(dat) <= n) dat.eb(dat[len(dat) - 1] * inv<mint>(len(dat))); return dat[n]; } template <class mint, class... Ts> mint fact_invs(Ts... xs) { return (mint(1) * ... * fact_inv<mint>(xs)); } template <typename mint, class Head, class... Tail> mint multinomial(Head &&head, Tail &&... tail) { return fact<mint>(head) * fact_invs<mint>(std::forward<Tail>(tail)...); } template <typename mint> mint C_dense(int n, int k) { static vvc<mint> C; static int H = 0, W = 0; auto calc = [&](int i, int j) -> mint { if (i == 0) return (j == 0 ? mint(1) : mint(0)); return C[i - 1][j] + (j ? C[i - 1][j - 1] : 0); }; if (W <= k) { FOR(i, H) { C[i].resize(k + 1); FOR(j, W, k + 1) { C[i][j] = calc(i, j); } } W = k + 1; } if (H <= n) { C.resize(n + 1); FOR(i, H, n + 1) { C[i].resize(W); FOR(j, W) { C[i][j] = calc(i, j); } } H = n + 1; } return C[n][k]; } template <typename mint, bool large = false, bool dense = false> mint C(ll n, ll k) { assert(n >= 0); if (k < 0 || n < k) return 0; if constexpr (dense) return C_dense<mint>(n, k); if constexpr (!large) return multinomial<mint>(n, k, n - k); k = min(k, n - k); mint x(1); FOR(i, k) x *= mint(n - i); return x * fact_inv<mint>(k); } template <typename mint, bool large = false> mint C_inv(ll n, ll k) { assert(n >= 0); assert(0 <= k && k <= n); if (!large) return fact_inv<mint>(n) * fact<mint>(k) * fact<mint>(n - k); return mint(1) / C<mint, 1>(n, k); } // [x^d](1-x)^{-n} template <typename mint, bool large = false, bool dense = false> mint C_negative(ll n, ll d) { assert(n >= 0); if (d < 0) return mint(0); if (n == 0) { return (d == 0 ? mint(1) : mint(0)); } return C<mint, large, dense>(n + d - 1, d); } #line 3 "/home/maspy/compro/library/mod/modint.hpp" template <int mod> struct modint { static constexpr u32 umod = u32(mod); static_assert(umod < u32(1) << 31); u32 val; static modint raw(u32 v) { modint x; x.val = v; return x; } constexpr modint() : val(0) {} constexpr modint(u32 x) : val(x % umod) {} constexpr modint(u64 x) : val(x % umod) {} constexpr modint(u128 x) : val(x % umod) {} constexpr modint(int x) : val((x %= mod) < 0 ? x + mod : x){}; constexpr modint(ll x) : val((x %= mod) < 0 ? x + mod : x){}; constexpr modint(i128 x) : val((x %= mod) < 0 ? x + mod : x){}; bool operator<(const modint &other) const { return val < other.val; } modint &operator+=(const modint &p) { if ((val += p.val) >= umod) val -= umod; return *this; } modint &operator-=(const modint &p) { if ((val += umod - p.val) >= umod) val -= umod; return *this; } modint &operator*=(const modint &p) { val = u64(val) * p.val % umod; return *this; } modint &operator/=(const modint &p) { *this *= p.inverse(); return *this; } modint operator-() const { return modint::raw(val ? mod - val : u32(0)); } modint operator+(const modint &p) const { return modint(*this) += p; } modint operator-(const modint &p) const { return modint(*this) -= p; } modint operator*(const modint &p) const { return modint(*this) *= p; } modint operator/(const modint &p) const { return modint(*this) /= p; } bool operator==(const modint &p) const { return val == p.val; } bool operator!=(const modint &p) const { return val != p.val; } modint inverse() const { int a = val, b = mod, u = 1, v = 0, t; while (b > 0) { t = a / b; swap(a -= t * b, b), swap(u -= t * v, v); } return modint(u); } modint pow(ll n) const { assert(n >= 0); modint ret(1), mul(val); while (n > 0) { if (n & 1) ret *= mul; mul *= mul; n >>= 1; } return ret; } static constexpr int get_mod() { return mod; } // (n, r), r は 1 の 2^n 乗根 static constexpr pair<int, int> ntt_info() { if (mod == 120586241) return {20, 74066978}; if (mod == 167772161) return {25, 17}; if (mod == 469762049) return {26, 30}; if (mod == 754974721) return {24, 362}; if (mod == 880803841) return {23, 211}; if (mod == 943718401) return {22, 663003469}; if (mod == 998244353) return {23, 31}; if (mod == 1045430273) return {20, 363}; if (mod == 1051721729) return {20, 330}; if (mod == 1053818881) return {20, 2789}; return {-1, -1}; } static constexpr bool can_ntt() { return ntt_info().fi != -1; } }; #ifdef FASTIO template <int mod> void rd(modint<mod> &x) { fastio::rd(x.val); x.val %= mod; // assert(0 <= x.val && x.val < mod); } template <int mod> void wt(modint<mod> x) { fastio::wt(x.val); } #endif using modint107 = modint<1000000007>; using modint998 = modint<998244353>; #line 2 "/home/maspy/compro/library/graph/base.hpp" template <typename T> struct Edge { int frm, to; T cost; int id; }; template <typename T = int, bool directed = false> struct Graph { static constexpr bool is_directed = directed; int N, M; using cost_type = T; using edge_type = Edge<T>; vector<edge_type> edges; vector<int> indptr; vector<edge_type> csr_edges; vc<int> 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<int> deg_array() { if (vc_deg.empty()) calc_deg(); return vc_deg; } pair<vc<int>, vc<int>> 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<int> new_idx; vc<bool> 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<T, directed> rearrange(vc<int> 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<T, directed> G(n); vc<int> 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 7 "main.cpp" #line 2 "/home/maspy/compro/library/poly/poly_taylor_shift.hpp" #line 2 "/home/maspy/compro/library/nt/primetable.hpp" template <typename T = int> vc<T> primetable(int LIM) { ++LIM; const int S = 32768; static int done = 2; static vc<T> 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<pair<int, int>> 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<bool, S> 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 <typename mint> vc<mint> powertable_1(mint a, ll N) { // table of a^i vc<mint> f(N + 1, 1); FOR(i, N) f[i + 1] = a * f[i]; return f; } // 0^e, ..., N^e template <typename mint> vc<mint> powertable_2(ll e, ll N) { auto primes = primetable(N); vc<mint> 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 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 <typename T, u32 p0, u32 p1, u32 p2> T CRT3(u64 a0, u64 a1, u64 a2) { static_assert(p0 < p1 && p1 < p2); static constexpr u64 x0_1 = mod_pow_constexpr(p0, p1 - 2, p1); static constexpr u64 x01_2 = mod_pow_constexpr(u64(p0) * p1 % p2, p2 - 2, p2); u64 c = (a1 - a0 + p1) * x0_1 % p1; u64 a = a0 + c * p0; c = (a2 - a % p2 + p2) * x01_2 % p2; return T(a) + T(c) * T(p0) * T(p1); } #line 2 "/home/maspy/compro/library/poly/convolution_naive.hpp" template <class T, typename enable_if<!has_mod<T>::value>::type* = nullptr> vc<T> convolution_naive(const vc<T>& a, const vc<T>& b) { int n = int(a.size()), m = int(b.size()); if (n > m) return convolution_naive<T>(b, a); if (n == 0) return {}; vector<T> ans(n + m - 1); FOR(i, n) FOR(j, m) ans[i + j] += a[i] * b[j]; return ans; } template <class T, typename enable_if<has_mod<T>::value>::type* = nullptr> vc<T> convolution_naive(const vc<T>& a, const vc<T>& b) { int n = int(a.size()), m = int(b.size()); if (n > m) return convolution_naive<T>(b, a); if (n == 0) return {}; vc<T> ans(n + m - 1); if (n <= 16 && (T::get_mod() < (1 << 30))) { for (int k = 0; k < n + m - 1; ++k) { int s = max(0, k - m + 1); int t = min(n, k + 1); u64 sm = 0; for (int i = s; i < t; ++i) { sm += u64(a[i].val) * (b[k - i].val); } ans[k] = sm; } } else { for (int k = 0; k < n + m - 1; ++k) { int s = max(0, k - m + 1); int t = min(n, k + 1); u128 sm = 0; for (int i = s; i < t; ++i) { sm += u64(a[i].val) * (b[k - i].val); } ans[k] = T::raw(sm % T::get_mod()); } } return ans; } #line 2 "/home/maspy/compro/library/poly/convolution_karatsuba.hpp" // 任意の環でできる template <typename T> vc<T> convolution_karatsuba(const vc<T>& f, const vc<T>& g) { const int thresh = 30; if (min(len(f), len(g)) <= thresh) return convolution_naive(f, g); int n = max(len(f), len(g)); int m = ceil(n, 2); vc<T> f1, f2, g1, g2; if (len(f) < m) f1 = f; if (len(f) >= m) f1 = {f.begin(), f.begin() + m}; if (len(f) >= m) f2 = {f.begin() + m, f.end()}; if (len(g) < m) g1 = g; if (len(g) >= m) g1 = {g.begin(), g.begin() + m}; if (len(g) >= m) g2 = {g.begin() + m, g.end()}; vc<T> a = convolution_karatsuba(f1, g1); vc<T> b = convolution_karatsuba(f2, g2); FOR(i, len(f2)) f1[i] += f2[i]; FOR(i, len(g2)) g1[i] += g2[i]; vc<T> c = convolution_karatsuba(f1, g1); vc<T> F(len(f) + len(g) - 1); assert(2 * m + len(b) <= len(F)); FOR(i, len(a)) F[i] += a[i], c[i] -= a[i]; FOR(i, len(b)) F[2 * m + i] += b[i], c[i] -= b[i]; if (c.back() == T(0)) c.pop_back(); FOR(i, len(c)) if (c[i] != T(0)) F[m + i] += c[i]; return F; } #line 2 "/home/maspy/compro/library/poly/ntt.hpp" template <class mint> void ntt(vector<mint>& a, bool inverse) { assert(mint::can_ntt()); const int rank2 = mint::ntt_info().fi; const int mod = mint::get_mod(); static array<mint, 30> root, iroot; static array<mint, 30> rate2, irate2; static array<mint, 30> rate3, irate3; 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<C> rts = {{0, 0}, {1, 0}}; vector<int> rev = {0, 1}; void ensure_base(int nbase) { if (nbase <= base) return; rev.resize(1 << nbase); rts.resize(1 << nbase); for (int i = 0; i < (1 << nbase); i++) { rev[i] = (rev[i >> 1] >> 1) + ((i & 1) << (nbase - 1)); } while (base < nbase) { real angle = PI * 2.0 / (1 << (base + 1)); for (int i = 1 << (base - 1); i < (1 << base); i++) { rts[i << 1] = rts[i]; real angle_i = angle * (2 * i + 1 - (1 << base)); rts[(i << 1) + 1] = C(cos(angle_i), sin(angle_i)); } ++base; } } void fft(vector<C>& a, int n) { assert((n & (n - 1)) == 0); int zeros = __builtin_ctz(n); ensure_base(zeros); int shift = base - zeros; for (int i = 0; i < n; i++) { if (i < (rev[i] >> shift)) { swap(a[i], a[rev[i] >> shift]); } } for (int k = 1; k < n; k <<= 1) { for (int i = 0; i < n; i += 2 * k) { for (int j = 0; j < k; j++) { C z = a[i + j + k] * rts[j + k]; a[i + j + k] = a[i + j] - z; a[i + j] = a[i + j] + z; } } } } } // namespace CFFT #line 9 "/home/maspy/compro/library/poly/convolution.hpp" template <class mint> vector<mint> convolution_ntt(vector<mint> a, vector<mint> b) { if (a.empty() || b.empty()) return {}; int n = int(a.size()), m = int(b.size()); int sz = 1; while (sz < n + m - 1) sz *= 2; // sz = 2^k のときの高速化。分割統治的なやつで損しまくるので。 if ((n + m - 3) <= sz / 2) { auto a_last = a.back(), b_last = b.back(); a.pop_back(), b.pop_back(); auto c = convolution(a, b); c.resize(n + m - 1); c[n + m - 2] = a_last * b_last; FOR(i, len(a)) c[i + len(b)] += a[i] * b_last; FOR(i, len(b)) c[i + len(a)] += b[i] * a_last; return c; } a.resize(sz), b.resize(sz); bool same = a == b; ntt(a, 0); if (same) { b = a; } else { ntt(b, 0); } FOR(i, sz) a[i] *= b[i]; ntt(a, 1); a.resize(n + m - 1); return a; } template <typename mint> vector<mint> convolution_garner(const vector<mint>& a, const vector<mint>& b) { int n = len(a), m = len(b); if (!n || !m) return {}; static constexpr int p0 = 167772161; static constexpr int p1 = 469762049; static constexpr int p2 = 754974721; using mint0 = modint<p0>; using mint1 = modint<p1>; using mint2 = modint<p2>; vc<mint0> a0(n), b0(m); vc<mint1> a1(n), b1(m); vc<mint2> a2(n), b2(m); FOR(i, n) a0[i] = a[i].val, a1[i] = a[i].val, a2[i] = a[i].val; FOR(i, m) b0[i] = b[i].val, b1[i] = b[i].val, b2[i] = b[i].val; auto c0 = convolution_ntt<mint0>(a0, b0); auto c1 = convolution_ntt<mint1>(a1, b1); auto c2 = convolution_ntt<mint2>(a2, b2); vc<mint> c(len(c0)); FOR(i, n + m - 1) { c[i] = CRT3<mint, p0, p1, p2>(c0[i].val, c1[i].val, c2[i].val); } return c; } template <typename R> vc<double> convolution_fft(const vc<R>& a, const vc<R>& b) { using C = CFFT::C; int need = (int)a.size() + (int)b.size() - 1; int nbase = 1; while ((1 << nbase) < need) nbase++; CFFT::ensure_base(nbase); int sz = 1 << nbase; vector<C> fa(sz); for (int i = 0; i < sz; i++) { 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<double> ret(need); for (int i = 0; i < need; i++) { ret[i] = (i & 1 ? fa[i >> 1].y : fa[i >> 1].x); } return ret; } vector<ll> convolution(const vector<ll>& a, const vector<ll>& b) { int n = len(a), m = len(b); if (!n || !m) return {}; if (min(n, m) <= 2500) return convolution_naive(a, b); ll abs_sum_a = 0, abs_sum_b = 0; ll LIM = 1e15; FOR(i, n) abs_sum_a = min(LIM, abs_sum_a + abs(a[i])); FOR(i, m) abs_sum_b = min(LIM, abs_sum_b + abs(b[i])); if (i128(abs_sum_a) * abs_sum_b < 1e15) { vc<double> c = convolution_fft<ll>(a, b); vc<ll> res(len(c)); FOR(i, len(c)) res[i] = ll(floor(c[i] + .5)); return res; } static constexpr unsigned long long MOD1 = 754974721; // 2^24 static constexpr unsigned long long MOD2 = 167772161; // 2^25 static constexpr unsigned long long MOD3 = 469762049; // 2^26 static constexpr unsigned long long M2M3 = MOD2 * MOD3; static constexpr unsigned long long M1M3 = MOD1 * MOD3; static constexpr unsigned long long M1M2 = MOD1 * MOD2; static constexpr unsigned long long M1M2M3 = MOD1 * MOD2 * MOD3; static const unsigned long long i1 = mod_inv(MOD2 * MOD3, MOD1); static const unsigned long long i2 = mod_inv(MOD1 * MOD3, MOD2); static const unsigned long long i3 = mod_inv(MOD1 * MOD2, MOD3); using mint1 = modint<MOD1>; using mint2 = modint<MOD2>; using mint3 = modint<MOD3>; vc<mint1> a1(n), b1(m); vc<mint2> a2(n), b2(m); vc<mint3> a3(n), b3(m); FOR(i, n) a1[i] = a[i], a2[i] = a[i], a3[i] = a[i]; FOR(i, m) b1[i] = b[i], b2[i] = b[i], b3[i] = b[i]; auto c1 = convolution_ntt<mint1>(a1, b1); auto c2 = convolution_ntt<mint2>(a2, b2); auto c3 = convolution_ntt<mint3>(a3, b3); vc<ll> c(n + m - 1); FOR(i, n + m - 1) { u64 x = 0; x += (c1[i].val * i1) % MOD1 * M2M3; x += (c2[i].val * i2) % MOD2 * M1M3; x += (c3[i].val * i3) % MOD3 * M1M2; ll diff = c1[i].val - ((long long)(x) % (long long)(MOD1)); if (diff < 0) diff += MOD1; static constexpr unsigned long long offset[5] = {0, 0, M1M2M3, 2 * M1M2M3, 3 * M1M2M3}; x -= offset[diff % 5]; c[i] = x; } return c; } template <typename mint> vc<mint> convolution(const vc<mint>& a, const vc<mint>& b) { int n = len(a), m = len(b); if (!n || !m) return {}; if (mint::can_ntt()) { if (min(n, m) <= 50) return convolution_karatsuba<mint>(a, b); return convolution_ntt(a, b); } if (min(n, m) <= 200) return convolution_karatsuba<mint>(a, b); return convolution_garner(a, b); } #line 5 "/home/maspy/compro/library/poly/poly_taylor_shift.hpp" // f(x) -> f(x+c) template <typename mint> vc<mint> poly_taylor_shift(vc<mint> f, mint c) { ll N = len(f); FOR(i, N) f[i] *= fact<mint>(i); auto b = powertable_1<mint>(c, N); FOR(i, N) b[i] *= fact_inv<mint>(i); reverse(all(f)); f = convolution(f, b); f.resize(N); reverse(all(f)); FOR(i, N) f[i] *= fact_inv<mint>(i); return f; } #line 2 "/home/maspy/compro/library/poly/fps_div.hpp" #line 2 "/home/maspy/compro/library/poly/count_terms.hpp" template<typename mint> int count_terms(const vc<mint>& f){ int t = 0; FOR(i, len(f)) if(f[i] != mint(0)) ++t; return t; } #line 4 "/home/maspy/compro/library/poly/fps_inv.hpp" template <typename mint> vc<mint> fps_inv_sparse(const vc<mint>& f) { int N = len(f); vc<pair<int, mint>> dat; FOR(i, 1, N) if (f[i] != mint(0)) dat.eb(i, f[i]); vc<mint> 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 <typename mint> vc<mint> fps_inv_dense_ntt(const vc<mint>& F) { vc<mint> G = {mint(1) / F[0]}; ll N = len(F), n = 1; G.reserve(N); while (n < N) { vc<mint> 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 <typename mint> vc<mint> fps_inv_dense(const vc<mint>& F) { if (mint::can_ntt()) return fps_inv_dense_ntt(F); const int N = len(F); vc<mint> R = {mint(1) / F[0]}; vc<mint> p; int m = 1; while (m < N) { p = convolution(R, R); p.resize(m + m); vc<mint> 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 <typename mint> vc<mint> fps_inv(const vc<mint>& f) { assert(f[0] != mint(0)); int n = count_terms(f); int t = (mint::can_ntt() ? 160 : 820); return (n <= t ? fps_inv_sparse<mint>(f) : fps_inv_dense<mint>(f)); } #line 5 "/home/maspy/compro/library/poly/fps_div.hpp" // f/g. f の長さで出力される. template <typename mint, bool SPARSE = false> vc<mint> fps_div(vc<mint> f, vc<mint> g) { if (SPARSE || count_terms(g) < 200) return fps_div_sparse(f, g); int n = len(f); g.resize(n); g = fps_inv<mint>(g); f = convolution(f, g); f.resize(n); return f; } // f/g ただし g は sparse template <typename mint> vc<mint> fps_div_sparse(vc<mint> f, vc<mint>& g) { if (g[0] != mint(1)) { mint cf = g[0].inverse(); for (auto&& x: f) x *= cf; for (auto&& x: g) x *= cf; } vc<pair<int, mint>> 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 <typename mint> void ntt_doubling(vector<mint>& a) { const int rank2 = mint::ntt_info().fi; static array<mint, 30> 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 <typename mint> mint coef_of_rational_fps_small(vector<mint> P, vector<mint> Q, ll N) { assert(len(Q) <= 16); int m = len(Q) - 1; assert(len(P) == m); if (m == 0) return mint(0); vc<u32> Q32(m + 1); FOR(i, m + 1) Q32[i] = (-Q[i]).val; using poly = vc<u64>; 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 <typename mint> mint coef_of_rational_fps_ntt(vector<mint> P, vector<mint> 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<int> 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<mint> S, T; while (N >= n) { mint w = inv<mint>(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 <typename mint> mint coef_of_rational_fps_convolution(vector<mint> P, vector<mint> Q, ll N) { P.resize(len(Q) - 1); if (len(P) == 0) return 0; while (N >= len(P)) { vc<mint> 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 <typename mint> mint coef_of_rational_fps(vector<mint> P, vector<mint> 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 1 "/home/maspy/compro/library/graph/tree_walk_generating_function.hpp" #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 <typename GT> struct Tree { using Graph_type = GT; GT &G; using WT = typename GT::cost_type; int N; vector<int> LID, RID, head, V, parent, VtoE; vc<int> depth; vc<WT> 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<int> heavy_path_at(int v) { vc<int> 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<int> collect_child(int v) { vc<int> res; for (auto &&e: G[v]) if (e.to != parent[v]) res.eb(e.to); return res; } vc<int> collect_light(int v) { vc<int> 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<pair<int, int>> get_path_decomposition(int u, int v, bool edge) { // [始点, 終点] の"閉"区間列。 vc<pair<int, int>> 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<int> restore_path(int u, int v) { vc<int> 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 <typename TREE> struct Static_TopTree { TREE &tree; vc<int> par, lch, rch, A, B; vc<bool> 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 <typename Data, typename F1, typename F2, typename F3, typename F4, typename F5> 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<pair<int, int>> 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 3 "/home/maspy/compro/library/graph/shortest_path/bfs01.hpp" template <typename T, typename GT> pair<vc<T>, vc<int>> bfs01(GT& G, int v) { assert(G.is_prepared()); int N = G.N; vc<T> dist(N, infty<T>); vc<int> par(N, -1); deque<int> 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<T> || 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 <typename T, typename GT> tuple<vc<T>, vc<int>, vc<int>> bfs01(GT& G, vc<int> vs) { assert(G.is_prepared()); int N = G.N; vc<T> dist(N, infty<T>); vc<int> par(N, -1); vc<int> root(N, -1); deque<int> 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<T> || 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/ds/unionfind/unionfind.hpp" struct UnionFind { int n, n_comp; vc<int> 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 4 "/home/maspy/compro/library/graph/characteristic_polynomial_of_tree_adjacency_matrix.hpp" // det(I-xA) の計算 (固有多項式の reverse になっている) // weight(i,j):A[i][j] // 偶数次だけしか出てこないので loop ありより高速 template <typename mint, typename F> vc<mint> characteristic_poly_of_tree_adjacency_matrix_not_allow_loop( Graph<int, 0>& G, F weight) { // int N = G.N; // vv(mint, A, N, N); // vv(mint, B, N, N); // FOR(i, N) A[i][i] = 1; // FOR(i, N) { // for (auto& e: G[i]) { B[i][e.to] = -weight(i, e.to); } // } // return det_A_plus_xB(A, B); using poly = vc<mint>; Tree<Graph<int, 0>> tree(G); Static_TopTree<decltype(tree)> STT(tree); using Data = array<array<poly, 2>, 2>; auto add = [&](poly& f, poly& g, int s, mint wt = 1) -> void { if (g.empty()) return; if (len(f) < len(g) + s) f.resize(len(g) + s); FOR(i, len(g)) f[s + i] += g[i] * wt; }; 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 { mint wt = -weight(u, v) * weight(v, u); Data Y; FOR(a, 2) { add(Y[0][0], X[a][0], 0); add(Y[1][1], X[a][0], 1, wt); add(Y[0][0], X[a][1], 0); } 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; add(Z[0][0], A, 0), add(Z[1][1], B, 0), add(Z[1][1], C, 0); return Z; }; auto merge_heavy = [&](Data& X, Data& Y, int va, int vb, int vc, int vd) -> Data { Data Z; mint wt = -weight(vb, vc) * weight(vc, vb); FOR(a, 2) FOR(d, 2) { poly f0 = X[a][0], &f1 = X[a][1]; poly g0 = Y[0][d], &g1 = Y[1][d]; // 辺を使う poly f = convolution(f0, g0); int x = (va != vb ? a : 1); int y = (vc != vd ? d : 1); add(Z[x][y], f, 1, wt); // 辺を使わない add(f0, f1, 0), add(g0, g1, 0); f = convolution(f0, g0); add(Z[a][d], f, 0); } return Z; }; Data X = STT.tree_dp<Data>(from_vertex, add_vertex, add_edge, merge_light, merge_heavy); vc<mint> ANS(G.N + 1); FOR(a, 2) FOR(b, 2) { FOR(i, len(X[a][b])) { ANS[2 * i] += X[a][b][i]; } } return ANS; } template <typename mint, typename F> vc<mint> characteristic_poly_of_tree_adjacency_matrix_allow_loop( Graph<int, 0>& G, F weight) { // 点とマッチングに分解 // マッチング:-w[i][j]w[j][i]x^2 // 点:1-w[i][i]x using poly = vc<mint>; Tree<Graph<int, 0>> tree(G); Static_TopTree<decltype(tree)> STT(tree); using Data = array<array<poly, 2>, 2>; auto add = [&](poly& f, poly& g, int s, mint wt = 1) -> void { if (g.empty()) return; if (len(f) < len(g) + s) f.resize(len(g) + s); FOR(i, len(g)) f[s + i] += g[i] * wt; }; auto from_vertex = [&](int v) -> Data { mint wt = weight(v, v); Data X; X[0][0] = poly{mint(1)}; X[1][1] = poly{mint(1), -wt}; return X; }; auto add_vertex = [&](Data& X, int v) -> Data { mint wt = weight(v, v); // 1-wtx add(X[1][1], X[0][0], 0, mint(1)); add(X[1][1], X[0][0], 1, -wt); return X; }; auto add_edge = [&](Data& X, int u, int v) -> Data { if (X[0][1].empty()) { X[1][0] = X[0][0]; } mint wt = weight(u, v) * weight(v, u); Data Y; add(Y[1][1], X[1][0], 2, -wt); add(Y[0][0], X[1][1], 0); 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; add(Z[0][0], A, 0), add(Z[1][1], B, 0), add(Z[1][1], C, 0); return Z; }; auto merge_heavy = [&](Data& X, Data& Y, int va, int vb, int vc, int vd) -> Data { Data Z; mint wt = weight(vb, vc) * weight(vc, vb); FOR(a, 2) FOR(b, 2) FOR(c, 2) FOR(d, 2) { bool non_use = 1; bool use = (b == 0) && (c == 0); if (va != vb && b == 0) non_use = 0; if (vc != vd && c == 0) non_use = 0; if (!non_use && !use) continue; poly f = convolution(X[a][b], Y[c][d]); if (non_use) add(Z[a][d], f, 0); if (use) { int x = (va != vb ? a : 1); int y = (vc != vd ? d : 1); add(Z[x][y], f, 2, -wt); } } return Z; }; Data X = STT.tree_dp<Data>(from_vertex, add_vertex, add_edge, merge_light, merge_heavy); poly& ANS = X[1][1]; return ANS; } // det(I-xA) の計算 (固有多項式の reverse になっている) // weight(i,j):A[i][j] template <bool ALLOW_LOOP, typename mint, typename F> vc<mint> characteristic_poly_of_tree_adjacency_matrix(Graph<int, 0>& G, F weight) { if constexpr (ALLOW_LOOP) { return characteristic_poly_of_tree_adjacency_matrix_allow_loop<mint>( G, weight); } else { return characteristic_poly_of_tree_adjacency_matrix_not_allow_loop<mint>( G, weight); } } #line 2 "/home/maspy/compro/library/poly/convolution_all.hpp" #line 4 "/home/maspy/compro/library/poly/convolution_all.hpp" template <typename T> vc<T> convolution_all(vc<vc<T>>& 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 4 "/home/maspy/compro/library/graph/tree_walk_generating_function.hpp" template <bool ALLOW_LOOP, typename mint, typename F> pair<vc<mint>, vc<mint>> tree_walk_generating_function(Graph<int, 0>& G, int s, int t, F weight) { int N = G.N; // 分母 auto f = characteristic_poly_of_tree_adjacency_matrix<ALLOW_LOOP, mint>( G, weight); // 分子 // (s,t) パスに沿って成分をかけたものの符号調整 + 他の成分 using poly = vc<mint>; vc<poly> polys; pair<int, mint> path_poly = {0, mint(1)}; vc<bool> on_path(N); auto [dist, par] = bfs01<int>(G, s); on_path[t] = 1; while (t != s) { mint w = weight(par[t], t); t = par[t], on_path[t] = 1; path_poly.fi += 1, path_poly.se *= w; // +wx } 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<int> comp(N); FOR(v, N) comp[uf[v]].eb(v); FOR(r, N) { if (on_path[r] || uf[r] != r) continue; vc<int>& V = comp[r]; Graph<int, 0> H = G.rearrange(V); poly f = characteristic_poly_of_tree_adjacency_matrix<ALLOW_LOOP, mint>( H, [&](int i, int j) -> mint { return weight(V[i], V[j]); }); polys.eb(f); } poly B = convolution_all<mint>(polys); for (auto& x: B) x *= path_poly.se; int m = path_poly.fi; poly g(len(B) + m); FOR(i, len(B)) g[m + i] = path_poly.se * B[i]; return {f, g}; } #line 11 "main.cpp" using mint = modint998; using poly = vc<mint>; void solve() { LL(N, M, S, T); --S, --T; Graph<int, 0> G(N); G.read_tree(); auto [f, g] = tree_walk_generating_function<false, mint>( G, S, T, [&](int i, int j) -> mint { return 1; }); // 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<mint> W = fps_div(g, f); FOR(m, N) W[m] *= fact_inv<mint>(m); vc<mint> tmp(N + 1); FOR(m, N + 1) tmp[m] = fact_inv<mint>(m); vc<mint> F = convolution(W, tmp); F.resize(N); FOR(i, N) F[i] *= fact<mint>(i); reverse(all(f)); f = poly_taylor_shift<mint>(f, -1); reverse(all(f)); g = convolution<mint>(F, f); g.resize(N); mint ANS = coef_of_rational_fps<mint>(g, f, M); print(ANS); } signed main() { int T = 1; // INT(T); FOR(T) solve(); return 0; }