#include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define TP template #define TN typename #define TE TP #define TES TP #define Z auto #define var const Z & #define ep emplace_back #define eb emplace #define fi first #define se second #define bg begin #define ed end #define all(x) bg(x), ed(x) #define OV(a, b, c, d, e, ...) e #define FO4(i, a, b, c) for (int i = (a); i < (b); i += (c)) #define FO3(i, a, b) FO4(i, a, b, 1) #define FO2(i, a) FO3(i, 0, a) #define FO1(a) FO2(_, a) #define FOR(...) OV(__VA_ARGS__, FO4, FO3, FO2, FO1)(__VA_ARGS__) #define FF4(i, a, b, c) for (int i = (b) - 1; i >= (a); i -= (c)) #define FF3(i, a, b) FF4(i, a, b, 1) #define FF2(i, a) FF3(i, 0, a) #define FF1(a) FF2(_, a) #define FOR_R(...) OV(__VA_ARGS__, FF4, FF3, FF2, FF1)(__VA_ARGS__) #define FOR_subset(t, s) for (int t = (s); t > -1; t = (t == 0 ? -1 : (t - 1) & s)) #define sort ranges::sort using namespace std; TE using vc = vector; TE using vvc = vc>; TE using T1 = tuple; TE using T2 = tuple; TE using T3 = tuple; TE using T4 = tuple; TE using max_heap = priority_queue; TE using min_heap = priority_queue, greater>; using u8 = unsigned char; using uint = unsigned int; using ll = long long; using ull = unsigned long long; using ld = long double; using i128 = __int128; using u128 = __uint128_t; using f128 = __float128; using u16 = uint16_t; using PII = pair; using PLL = pair; using vi = vc; using vl = vc; #ifdef YRSD constexpr bool dbg = 1; #else constexpr bool dbg = 0; #endif TES concept nof = (not same_as and ...); TE constexpr bool can_in = 0; TE constexpr bool can_out = 0; TP<> constexpr bool can_in = 1; TP<> constexpr bool can_out = 1; istream &operator>>(istream &I, i128 &x) { static string s; I >> s; int f = s[0] == '-'; x = 0; const int N = (int)s.size(); FOR(i, f, N) x = x * 10 + s[i] - '0'; if (f) x = -x; return I; } ostream &operator<<(ostream &O, i128 x) { static string s; s.clear(); bool f = x < 0; if (f) x = -x; while (x) s += '0' + x % 10, x /= 10; if (s.empty()) s += '0'; if (f) s += '-'; reverse(all(s)); return O << s; } istream &operator>>(istream &I, f128 &x) { static string s; I >> s, x = stold(s); return I; } ostream &operator<<(ostream &O, const f128 x) { return O << ld(x); } TP requires(can_in) I &operator>>(I &in, tuple &a) { apply([&in](Z &...s) { ((in >> s), ...); }, a); return in; } TP requires(can_in) I &operator>>(I &in, pair &x) { return in >> x.fi >> x.se; } TP requires(can_out) U &operator<<(U &out, const pair &x) { return out << x.fi << ' ' << x.se; } TP requires(can_in) I &operator>>(I &in, vc &a) { for (Z &x : a) in >> x; return in; } TP requires(can_out) U &operator<<(U &out, const vc &a) { if (a.empty()) return out; Z i = bg(a); out << *i++; for (; i != ed(a); ++i) out << ' ' << *i; return out; } TP requires(can_in) I &operator>>(I &in, array &a) { FOR(i, N) in >> a[i]; return in; } TP requires(can_out) U &operator<<(U &out, const array &a) { out << a[0]; FOR(i, 1, N) out << ' ' << a[i]; return out; } void IN() {} TE void IN(T &x, Z &...s) { cin >> x, IN(s...); } void print() { cout << '\n'; } TES void print(T &&x, S &&...y) { cout << x; if constexpr (sizeof...(S)) cout << ' '; print(forward(y)...); } void put() {} TES void put(T &&x, S &&...y) { cout << x; put(forward(y)...); } #define INT(...) int __VA_ARGS__; IN(__VA_ARGS__) #define UINT(...) uint __VA_ARGS__; IN(__VA_ARGS__) #define LL(...) ll __VA_ARGS__; IN(__VA_ARGS__) #define ULL(...) ull __VA_ARGS__; IN(__VA_ARGS__) #define I128(...) i128 __VA_ARGS__; IN(__VA_ARGS__) #define STR(...) string __VA_ARGS__; IN(__VA_ARGS__) #define CH(...) char __VA_ARGS__; IN(__VA_ARGS__) #define REAL(...) re __VA_ARGS__; IN(__VA_ARGS__) #define VEC(T, a, n) vc a(n); IN(a) void YES(bool o = 1) { print(o ? "YES" : "NO"); } void Yes(bool o = 1) { print(o ? "Yes" : "No"); } void yes(bool o = 1) { print(o ? "yes" : "no"); } void NO(bool o = 1) { YES(not o); } void No(bool o = 1) { Yes(not o); } void no(bool o = 1) { yes(not o); } void ALICE(bool o = 1) { print(o ? "ALICE" : "BOB"); } void Alice(bool o = 1) { print(o ? "Alice" : "Bob"); } void alice(bool o = 1) { print(o ? "alice" : "bob"); } void BOB(bool o = 1) { ALICE(not o); } void Bob(bool o = 1) { Alice(not o); } void bob(bool o = 1) { alice(not o); } void POSSIBLE(bool o = 1) { print(o ? "POSSIBLE" : "IMPOSSIBLE"); } void Possible(bool o = 1) { print(o ? "Possible" : "Impossible"); } void possible(bool o = 1) { print(o ? "possible" : "impossible"); } void IMPOSSIBLE(bool o = 1) { POSSIBLE(not o); } void Impossible(bool o = 1) { Possible(not o); } void impossible(bool o = 1) { possible(not o); } void TAK(bool o = 1) { print(o ? "TAK" : "NIE"); } void NIE(bool o = 1) { TAK(not o); } #if (__cplusplus >= 202002L) #include constexpr ld pi = numbers::pi_v; #endif TE constexpr T inf = numeric_limits::max(); template <> constexpr i128 inf = i128(inf) * 2'000'000'000'000'000'000; template constexpr pair inf> = {inf, inf}; TE constexpr static inline int pc(T x) { return popcount(make_unsigned_t(x)); } constexpr static inline ll si(var a) { return a.size(); } void reverse(Z &a) { reverse(all(a)); } void unique(Z &a) { sort(a); a.erase(unique(all(a)), ed(a)); } TE vc inverse(const vc &a) { int N = si(a); vc b(N, -1); FOR(i, N) if (a[i] != -1) b[a[i]] = i; return b; } Z QMAX(var a) { return *max_element(all(a)); } Z QMIN(var a) { return *min_element(all(a)); } TE Z QMAX(T l, T r) { return *max_element(l, r); } TE Z QMIN(T l, T r) { return *min_element(l, r); } constexpr bool chmax(Z &a, var b) { return (a < b ? a = b, 1 : 0); } constexpr bool chmin(Z &a, var b) { return (a > b ? a = b, 1 : 0); } vc argsort(var a) { vc I(si(a)); iota(all(I), 0); sort(I, [&](int i, int k) { return a[i] < a[k] or (a[i] == a[k] and i < k); }); return I; } TE vc rearrange(const vc &a, const vc &I) { int N = si(I); vc b(N); FOR(i, N) b[i] = a[I[i]]; return b; } template vc pre_sum(const vc &a) { int N = si(a); vc c(N + 1); FOR(i, N) c[i + 1] = c[i] + a[i]; if (of == 0) c.erase(bg(c)); return c; } TE constexpr static int topbit(T x) { if (x == 0) return -1; if constexpr (sizeof(T) <= 4) return 31 - __builtin_clz(x); else return 63 - __builtin_clzll(x); } TE constexpr static int lowbit(T x) { if (x == 0) return -1; if constexpr (sizeof(T) <= 4) return __builtin_ctz(x); else return __builtin_ctzll(x); } TE constexpr inline T floor(T x, T y) { return x / y - (x % y and (x ^ y) < 0); } TE constexpr inline T ceil(T x, T y) { return floor(x + y - 1, y); } TE constexpr inline T bmod(T x, T y) { return x - floor(x, y) * y; } TE constexpr inline pair divmod(T x, T y) { T q = floor(x, y); return pair{q, x - q * y}; } TE T SUM(var v) { return accumulate(all(v), T()); } TE T SUM(Z l, Z r) { return accumulate(l, r, T()); } int lb(var a, Z x) { return lower_bound(all(a), x) - a.begin(); } TE int lb(T l, T r, Z x) { return lower_bound(l, r, x) - l; } int ub(var a, Z x) { return upper_bound(all(a), x) - a.begin(); } TE int ub(T l, T r, Z x) { return upper_bound(l, r, x) - l; } template ll bina(Z f, ll l, ll r) { if (ck) assert(f(l)); while (abs(l - r) > 1) { ll x = (r + l) >> 1; (f(x) ? l : r) = x; } return l; } TE T bina_real(Z f, T l, T r, int c = 100) { while (c--) { T x = (l + r) / 2; (f(x) ? l : r) = x; } return (l + r) / 2; } TE T pop(vc &a) { T x = a.back(); a.pop_back(); return x; } TE T pop(max_heap &q) { T x = q.top(); q.pop(); return x; } TE T pop(min_heap &q) { T x = q.top(); q.pop(); return x; } char pop(string &s) { char x = s.back(); s.pop_back(); return x; } void setp(int x) { cout << fixed << setprecision(x); } TE inline void sh(vc &a, int N, T b = {}) { a.resize(N, b); } namespace fio { static constexpr uint sz = 1 << 17; char a[sz]; char b[sz]; char t[100]; uint l = 0, r = 0, pr = 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(a, a + l, r - l); r = r - l + fread(a + r - l, 1, sz - r + l, stdin); l = 0; if (r < sz) a[r++] = '\n'; } inline void flush() { fwrite(b, 1, pr, stdout), pr = 0; } inline void rd(char &c) { do { if (l + 1 > r) load(); c = a[l++]; } while (isspace(c)); } inline void rd(string &s) { s.clear(); char c; do { if (l + 1 > r) load(); c = a[l++]; } while (isspace(c)); do { s += c; if (l == r) load(); c = a[l++]; } while (!isspace(c)); } TE inline void rd_re(T &x) { static string s; rd(s); x = stod(s); } TE inline void rd_inte(T &x) { if (l + 100 > r) load(); char c; do c = a[l++]; while (c < '-'); bool op = 0; if constexpr (is_signed_v or is_same_v) { if (c == '-') op = 1, c = a[l++]; } x = 0; while ('0' <= c) x = x * 10 + (c & 15), c = a[l++]; if constexpr (is_signed_v or is_same_v) { if (op) x = -x; } } struct Fin { inline Fin &operator>>(char &c) { rd(c); return *this; } inline Fin &operator>>(string &s) { rd(s); return *this; } TE requires(is_integral_v or is_same_v or is_same_v) inline Fin &operator>>(T &x) { rd_inte(x); return *this; } TE requires(is_floating_point_v or is_same_v) inline Fin &operator>>(T &x){ rd_re(x); return *this; } } fin; inline void wt(char c) { if (pr == sz) flush(); b[pr++] = c; } inline void wt(const string &s) { for (char c : s) wt(c); } inline void wt(const char *s) { size_t si = strlen(s); for (size_t i = 0; i < si; i++) wt(s[i]); } TE inline void wt_inte(T x) { if (pr > sz - 100) flush(); if (x < 0) b[pr++] = '-', x = -x; int outi = 96; for (; x >= 10000; outi -= 4) { memcpy(t + outi, pre.num[x % 10000], 4); x /= 10000; } if (x >= 1000) { memcpy(b + pr, pre.num[x], 4); pr += 4; } else if (x >= 100) { memcpy(b + pr, pre.num[x] + 1, 3); pr += 3; } else if (x >= 10) { int q = (x * 103) >> 10; b[pr] = q | '0'; b[pr + 1] = (x - q * 10) | '0'; pr += 2; } else b[pr++] = x | '0'; memcpy(b + pr, t + outi + 4, 96 - outi); pr += 96 - outi; } int w = 10; TE inline void wt_real(T x) { ostringstream oss; oss << fixed << setprecision(w) << double(x); string s = oss.str(); wt(s); } struct Fout { void setp(int x) { w = x; } inline Fout &operator<<(const char &c) { wt(c); return *this; } inline Fout &operator<<(const string &s) { wt(s); return *this; } TE requires(is_integral_v or is_same_v or is_same_v) inline Fout &operator<<(const T &x) { wt_inte(x); return *this; } TE requires(is_floating_point_v or is_same_v) inline Fout &operator<<(const T &x) { wt_real(x); return *this; } } fout; inline void __attribute__((destructor)) _d() { flush(); } inline void sc() {} TE inline void sc(T &x, Z &...s) { fin >> x, sc(s...); } void inline pt() { fout << '\n'; } TES inline void pt(T &&x, S &&...y) { fout << x; if constexpr (sizeof...(S)) fout << ' '; pt(forward(y)...); } void inline pu() {} TES inline void pu(T &&x, S &&...y) { fout << x; pu(forward(y)...); } } template <> constexpr bool can_in = 1; template <> constexpr bool can_out = 1; #define setp(x) fio::fout.setp(x) #define IN fio::sc #define print fio::pt #define put fio::pu struct dsu { int c; vc fa; dsu(int N = 0) : c(N), fa(N, -1) {} int f(int x) { while (fa[x] >= 0) { int p = fa[fa[x]]; if (p < 0) return fa[x]; x = fa[x] = p; } return x; } int operator[](int x) { return f(x); } bool merge(int x, int y) { x = f(x), y = f(y); if (x == y) return 0; if (fa[x] > fa[y]) swap(x, y); fa[x] += fa[y]; fa[y] = x; --c; return 1; } bool set(int x, int y) { x = f(x), y = f(y); if (x == y) return 0; fa[x] += fa[y]; fa[y] = x; --c; return 1; } int size(int x) { return -fa[f(x)]; } int count() const { return c; } bool same(int x, int y) { return f(x) == f(y); } void build(int N) { fa.assign(N, -1), c = N; } void reset() { fill(all(fa), -1), c = si(fa); } vc> group() { int N = si(fa); vc> v(N), s; FOR(i, N) v[f(i)].ep(i); FOR(i, N) if (not v[i].empty()) s.ep(v[i]); return s; } void pr() { int N = si(fa); vc res(N); FOR(i, N) res[i] = f(i); print("fa:", res); } }; TE struct hashmap { uint ls, ms; vc a; vc b; vc vis; ull hash(ull x) const { static const ull bs = chrono::steady_clock::now().time_since_epoch().count(); x += bs; x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9; x = (x ^ (x >> 27)) * 0x94d049bb133111eb; return (x ^ (x >> 31)) & ms; } void extend() { vc> s; int N = si(vis); s.reserve(N / 2 - ls); FOR(i, N) if (vis[i]) s.ep(a[i], b[i]); build(si(s) << 1); for (var [l, r] : s) (*this)[l] = r; } hashmap(uint N = 0) { build(N); } void build(uint N) { uint k = 8; while (k < (N << 1)) k <<= 1; ls = k >> 1, ms = k - 1; a.resize(k); b.resize(k); vis.assign(k, 0); } void clear() { fill(all(vis), 0); ls = (ms + 1) >> 1; } ll size() const { return vis.size() / 2 - ls; } int id(ull k) const { int i = hash(k); while (vis[i] and a[i] != k) i = (i + 1) & ms; return i; } T &operator[](ull k) { if (ls == 0) extend(); int i = id(k); if (not vis[i]) { vis[i] = 1; a[i] = k; b[i] = T(); --ls; } return b[i]; } T get(ull k, T fl) const { int i = id(k); return (vis[i] ? b[i] : fl); } bool contains(ull k) const { int i = id(k); return vis[i] and a[i] == k; } vc> get_all() const { int N = si(vis); vc> s; FOR(i, N) if (vis[i]) s.ep(a[i], b[i]); return s; } }; TE struct edge { int f, to; T w; int id; operator int() const { return to; } }; template struct graph { static constexpr bool is_dir = dir; int N, M; using cost_type = T; using ee = edge; vc es; vc in; vc c; bool ok; bool isok() { return ok; } struct px { const graph *g; int l, r; px(const graph *g, int l, int r) : g(g), l(l), r(r) {} const ee *begin() const { if (l == r) return 0; return &g->c[l]; } const ee *end() const { if (l == r) return 0; return &g->c[r]; } }; px operator[](int i) const { assert(ok); return {this, in[i], in[i + 1]}; } graph() : N(0), M(0), ok(0) {} graph(int N) : N(N), M(0), ok(0) {} void add(int f, int t, T w = 1, int i = -1) { assert(not ok); assert(-1 < f and -1 < t and t < N and f < N); if (i == -1) i = M; es.ep(ee{f, t, w, i}); ++M; } void build() { assert(not ok); ok = 1; in.assign(N + 1, 0); for (Z &&e : es) { in[e.f + 1]++; if (not dir) in[e.to + 1]++; } FOR(i, N) in[i + 1] += in[i]; Z cc = in; c.resize(in.back() + 1); for (Z &&e : es) { c[cc[e.f]++] = e; if (not dir) c[cc[e.to]++] = {e.to, e.f, e.w, e.id}; } } template void sc() { sc(N - 1); } template void sc(int M) { es.reserve(M * (dir ? 1 : 2)); FOR(M) { INT(x, y); x -= of, y -= of; if (not wt) { add(x, y); } else { T w; IN(w); add(x, y, w); } } build(); } vc deg() { vc a(N); for (Z &&e : es) ++a[e.f], ++a[e.to]; return a; } pair, vc> deg_inout() { vc a(N), b(N); for (Z &&e : es) ++a[e.to], ++b[e.f]; return {a, b}; } vc ni; vc vis; graph rearrange(const vc &v, bool keep_eid = 0) { if (si(ni) != N) ni.assign(N, -1); int N = si(v); FOR(i, N) ni[v[i]] = i; graph g(N); vc s; FOR(i, N) { for (Z &&e : (*this)[v[i]]) { if (si(vis) <= e.id) vis.resize(e.id + 1); if (vis[e.id]) continue; int f = e.f, to = e.to; if (ni[f] != -1 and ni[to] != -1) { s.ep(e.id); vis[e.id] = 1; int id = (keep_eid ? e.id : -1); g.add(ni[f], ni[to], e.w, id); } } } FOR(i, N) ni[v[i]] = -1; for (int i : s) vis[i] = 0; return g.build(), g; } ull has(ull x, ull y) { if (not dir and x > y) swap(x, y); return x * N + y; } hashmap mp; int get_eid(ull x, ull y) { if (mp.size() == 0) { mp.build(N - 1); for (Z &&e : es) { ull x = e.f, y = e.to; ull k = has(x, y); mp[k] = e.id; } } return mp.get(has(x, y), -1); } graph rev() const requires(dir) { graph ng(N); for (Z &&[f, t, w, id] : es) ng.add(t, f, w, id); return ng; } }; TE struct hld { using G = graph; G &g; int N, t = 0; vc L, R, hd, V, fa, to, d; hld(G &g, int r = 0) : g(g), N(g.N), L(N, -1), R(L), hd(N, r), V(L), fa(L), to(L), d(N) { if (r == -1) return; assert(g.isok()); dfs(r, -1); hl(r, r); } void dfs(int n, int f) { fa[n] = f; R[n] = 1; int l = g.in[n], r = g.in[n + 1], m = 0; Z &c = g.c; if (r - l > 1 and c[l].to == f) swap(c[l], c[l + 1]); FOR(i, l, r) if (c[i].to != f) { Z e = c[i]; to[e.to] = e.id; d[e.to] = d[n] + 1; dfs(e.to, n); R[n] += R[e.to]; if (chmax(m, R[e.to]) and l < i) swap(c[l], c[i]); } } void hl(int n, int p) { R[n] += L[n] = t; V[t++] = n; bool f = 1; for (Z &&e : g[n]) if (e.to != p) { hd[e.to] = f ? hd[n] : e.to; f = 0; hl(e.to, n); } } vc hp(int n) { vc s{n}; while (1) { int x = hc(s.back()); if (x == -1 or hd[x] != n) return s; s.ep(x); } } inline int hc(int x) { int i = L[x] + 1; if (i == N) return -1; int a = V[i]; return fa[a] == x ? a : -1; } int ev(int i) { Z &e = g.es[i]; return (fa[e.f] == e.to ? e.f : e.to); } int ve(int x) { return to[x]; } int gei(int x, int y) { if (fa[x] != y) swap(x, y); assert(fa[x] == y); return to[x]; } int el(int i) { return 2 * L[i] - d[i]; } int er(int i) { return 2 * R[i] - d[i] - 1; } int la(int n, int k) { assert(k <= d[n]); while (1) { int x = hd[n]; if (L[n] - k >= L[x]) return V[L[n] - k]; k -= L[n] - L[x] + 1; n = fa[x]; } } int lca(int x, int y) { for (;; y = fa[hd[y]]) { if (L[x] > L[y]) swap(x, y); if (hd[x] == hd[y]) return x; } } int dist(int a, int b) { return d[a] + d[b] - 2 * d[lca(a, b)]; } int meet(int a, int b, int c) { return lca(a, b) ^ lca(a, c) ^ lca(b, c); } bool ins(int x, int y) { return L[y] <= L[x] and L[x] < R[y]; } int jump(int x, int y, int k) { if (k == 1) { if (x == y) return -1; return ins(y, x) ? la(y, d[y] - d[x] - 1) : fa[x]; } int c = lca(x, y), a = d[x] - d[c], b = d[y] - d[c]; if (k > a + b) return -1; if (k <= a) return la(x, k); return la(y, a + b - k); } int size(int x, int r = -1) { if (r == -1) return R[x] - L[x]; if (x == r) return N; int y = jump(x, r, 1); if (ins(x, y)) return R[x] - L[x]; return N - R[y] + L[y]; } vc size_arr(int r = -1) { vc sz(N); FOR(i, N) sz[i] = size(i, r); return sz; } vc cc(int n) { static vc s; s.clear(); for (Z &&e : g[n]) if (e.to != fa[n]) s.ep(e.to); return s; } vc cl(int n) { static vc s; s.clear(); bool f = 1; for (Z &&e : g[n]) { if (e.to != fa[n]) { if (not f) s.ep(e.to); f = 0; } } return s; } vc dec(int x, int y, bool e) { vc a, b; while (1) { if (hd[x] == hd[y]) break; if (L[x] < L[y]) { b.ep(L[hd[y]], L[y]); y = fa[hd[y]]; } else { a.ep(L[x], L[hd[x]]); x = fa[hd[x]]; } } if (L[x] < L[y]) b.ep(L[x] + e, L[y]); else if (L[y] + e <= L[x]) a.ep(L[x], L[y] + e); reverse(b); a.insert(a.end(), all(b)); return a; } vc rest_path(int x, int y) { vc s; for (Z [a, b] : dec(x, y, 0)) { if (a <= b) FOR(i, a, b + 1) s.ep(V[i]); else FOR_R(i, b, a + 1) s.ep(V[i]); } return s; } PII cross(int a, int b, int c, int d) { int ab = lca(a, b), ac = lca(a, c), ad = lca(a, d); int bc = lca(b, c), bd = lca(b, d), cd = lca(c, d); int x = ab ^ ac ^ bc, y = ab ^ ad ^ bd; if (x != y) return {x, y}; int z = ac ^ ad ^ cd; if (x != z) x = -1; return {x, x}; } int max_path(Z f, int x, int y) { if (not f(x)) return -1; for (Z [a, b] : dec(x, y, 0)) { if (not f(V[a])) return x; if (f(V[b])) { x = V[b]; continue; } int c = bina<0>([&](int c) -> bool { return f(V[c]); }, a, b); return V[c]; } return x; } }; struct func_g { int N; vc to; graph g; vc rs; hld v; void gen() { dsu f(N); FOR(i, N) if (not f.merge(i, to[i])) rs[i] = i; FOR(i, N) if (rs[i] == i) rs[f[i]] = i; FOR(i, N) rs[i] = rs[f[i]]; FOR(i, N) { if (rs[i] == i) g.add(N, i); else g.add(to[i], i); } g.build(); } func_g(const vc &to) : N(si(to)), to(to), g(N + 1), rs(N, -1), v(g, (gen(), N)) {} int dist(int a, int b) { if (v.ins(a, b)) return v.d[a] - v.d[b]; int r = rs[a], t = to[r]; if (v.ins(t, b)) return v.d[a] - v.d[r] + 1 + v.d[t] - v.d[b]; return inf; } int jump(int n, ll k) { int d = v.d[n]; if (k < d) return v.jump(n, N, k); n = rs[n]; k -= d - 1; int t = to[n], c = v.d[t]; k %= c; if (k == 0) return n; return v.jump(t, N, k - 1); } vc jump_all(ll k) { vc res(N, -1); vc> q(N); FOR(n, N) { int d = v.d[n], r = rs[n]; if (d - 1 > k) q[n].ep(n, k); if (d - 1 <= k) { ll kk = k - d + 1; int t = to[r], c = v.d[t]; kk %= c; if (kk == 0) { res[n] = r; continue; } q[t].ep(n, kk - 1); } } vc pa; Z f = [&](Z &f, int n, int p) -> void { pa.ep(n); for (var [w, k] : q[n]) res[w] = ed(pa)[-1 - k]; for (int x : g[n]) if (x != p) f(f, x, n); pop(pa); }; for (int x : g[N]) f(f, x, N); return res; } bool inc(int n) { int r = rs[n]; if (to[r] == r) return n == r; return v.ins(to[r], n); } vc cc(int n) { assert(n == rs[n]); vc s{to[n]}; while (s.back() != n) s.ep(to[s.back()]); return s; } int meet_time(int i, int k) { if (i == k) return 0; if (rs[i] != rs[k]) return -1; int r = rs[i], b = to[r], n = v.d[b] - v.d[r] + 1; if ((v.d[i] - v.d[k]) % n != 0) return -1; if (v.d[i] == v.d[k]) return v.d[i] - v.d[v.lca(i, k)]; int x = v.d[i] - v.d[v.lca(b, i)]; int y = v.d[k] - v.d[v.lca(b, k)]; return max(x, y); } }; void Yorisou() { INT(N, K); VEC(ll, a, N); a.insert(ed(a), all(a)); pop(a); print(bina([&](ll lm) -> bool { int r = 0; ll s = 0; vc to(N + N + 1, N + N); FOR(l, N + N - 1) { while (r - l < N and r < N + N - 1 and s < lm) s += a[r++]; if (s >= lm) to[l] = r; s -= a[l]; } to = func_g(to).jump_all(K); FOR(i, N) if (to[i] - i <= N) return 1; return 0; }, 0, SUM(a) / K + 1)); } int main() { Yorisou(); return 0; }