結果
問題 |
No.3206 う し た ウ ニ 木 あ く ん 笑
|
ユーザー |
![]() |
提出日時 | 2025-07-19 18:19:33 |
言語 | C++23 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 306 ms / 3,000 ms |
コード長 | 8,087 bytes |
コンパイル時間 | 3,784 ms |
コンパイル使用メモリ | 304,476 KB |
実行使用メモリ | 86,712 KB |
最終ジャッジ日時 | 2025-07-19 18:19:42 |
合計ジャッジ時間 | 8,847 ms |
ジャッジサーバーID (参考情報) |
judge3 / judge5 |
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ファイルパターン | 結果 |
---|---|
sample | AC * 2 |
other | AC * 30 |
ソースコード
#line 2 "/Users/noya2/Desktop/Noya2_library/template/template.hpp" using namespace std; #include<bits/stdc++.h> #line 1 "/Users/noya2/Desktop/Noya2_library/template/inout_old.hpp" namespace noya2 { template <typename T, typename U> ostream &operator<<(ostream &os, const pair<T, U> &p){ os << p.first << " " << p.second; return os; } template <typename T, typename U> istream &operator>>(istream &is, pair<T, U> &p){ is >> p.first >> p.second; return is; } template <typename T> ostream &operator<<(ostream &os, const vector<T> &v){ int s = (int)v.size(); for (int i = 0; i < s; i++) os << (i ? " " : "") << v[i]; return os; } template <typename T> istream &operator>>(istream &is, vector<T> &v){ for (auto &x : v) is >> x; return is; } void in() {} template <typename T, class... U> void in(T &t, U &...u){ cin >> t; in(u...); } void out() { cout << "\n"; } template <typename T, class... U, char sep = ' '> void out(const T &t, const U &...u){ cout << t; if (sizeof...(u)) cout << sep; out(u...); } template<typename T> void out(const vector<vector<T>> &vv){ int s = (int)vv.size(); for (int i = 0; i < s; i++) out(vv[i]); } struct IoSetup { IoSetup(){ cin.tie(nullptr); ios::sync_with_stdio(false); cout << fixed << setprecision(15); cerr << fixed << setprecision(7); } } iosetup_noya2; } // namespace noya2 #line 1 "/Users/noya2/Desktop/Noya2_library/template/const.hpp" namespace noya2{ const int iinf = 1'000'000'007; const long long linf = 2'000'000'000'000'000'000LL; const long long mod998 = 998244353; const long long mod107 = 1000000007; const long double pi = 3.14159265358979323; const vector<int> dx = {0,1,0,-1,1,1,-1,-1}; const vector<int> dy = {1,0,-1,0,1,-1,-1,1}; const string ALP = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"; const string alp = "abcdefghijklmnopqrstuvwxyz"; const string NUM = "0123456789"; void yes(){ cout << "Yes\n"; } void no(){ cout << "No\n"; } void YES(){ cout << "YES\n"; } void NO(){ cout << "NO\n"; } void yn(bool t){ t ? yes() : no(); } void YN(bool t){ t ? YES() : NO(); } } // namespace noya2 #line 2 "/Users/noya2/Desktop/Noya2_library/template/utils.hpp" #line 6 "/Users/noya2/Desktop/Noya2_library/template/utils.hpp" namespace noya2{ unsigned long long inner_binary_gcd(unsigned long long a, unsigned long long b){ if (a == 0 || b == 0) return a + b; int n = __builtin_ctzll(a); a >>= n; int m = __builtin_ctzll(b); b >>= m; while (a != b) { int mm = __builtin_ctzll(a - b); bool f = a > b; unsigned long long c = f ? a : b; b = f ? b : a; a = (c - b) >> mm; } return a << std::min(n, m); } template<typename T> T gcd_fast(T a, T b){ return static_cast<T>(inner_binary_gcd(std::abs(a),std::abs(b))); } long long sqrt_fast(long long n) { if (n <= 0) return 0; long long x = sqrt(n); while ((x + 1) * (x + 1) <= n) x++; while (x * x > n) x--; return x; } template<typename T> T floor_div(const T n, const T d) { assert(d != 0); return n / d - static_cast<T>((n ^ d) < 0 && n % d != 0); } template<typename T> T ceil_div(const T n, const T d) { assert(d != 0); return n / d + static_cast<T>((n ^ d) >= 0 && n % d != 0); } template<typename T> void uniq(std::vector<T> &v){ std::sort(v.begin(),v.end()); v.erase(unique(v.begin(),v.end()),v.end()); } template <typename T, typename U> inline bool chmin(T &x, U y) { return (y < x) ? (x = y, true) : false; } template <typename T, typename U> inline bool chmax(T &x, U y) { return (x < y) ? (x = y, true) : false; } template<typename T> inline bool range(T l, T x, T r){ return l <= x && x < r; } } // namespace noya2 #line 8 "/Users/noya2/Desktop/Noya2_library/template/template.hpp" #define rep(i,n) for (int i = 0; i < (int)(n); i++) #define repp(i,m,n) for (int i = (m); i < (int)(n); i++) #define reb(i,n) for (int i = (int)(n-1); i >= 0; i--) #define all(v) (v).begin(),(v).end() using ll = long long; using ld = long double; using uint = unsigned int; using ull = unsigned long long; using pii = pair<int,int>; using pll = pair<ll,ll>; using pil = pair<int,ll>; using pli = pair<ll,int>; namespace noya2{ /* ~ (. _________ . /) */ } using namespace noya2; #line 2 "c.cpp" #line 2 "/Users/noya2/Desktop/Noya2_library/tree/rerootingdp.hpp" #line 5 "/Users/noya2/Desktop/Noya2_library/tree/rerootingdp.hpp" #include <ranges> namespace noya2 { // g[from] contains outgoing edges (to, edgeid(from, to)) // (E, op, e) is commutative monoid // ~edgeid(from, to) == edgeid(to, from) // return calculator of dp(r, v) template<class V, class E> auto rerootingdp(auto op, E e, auto put_edge, auto put_vertex, const std::vector<std::vector<std::pair<int, int>>> &g, int root = 0){ struct dp { // dp(r, v) : root is r, dp of subtree v // ans[v] = dp(v, v) // from[v] = dp(v, par(v)) // to[v] = dp(par(v), v) // from[root] and to[root] is undefined std::vector<V> ans, from, to; std::vector<int> down, up; std::vector<std::vector<int>> childs; bool is_in_subtree(int r, int v){ return down[r] < down[v] && up[v] <= up[r]; } V operator()(int r, int v){ if (r == v) return ans[v]; if (!is_in_subtree(v, r)) return to[v]; int le = 0, ri = childs[v].size(); while (ri - le > 1){ int md = (le + ri) / 2; if (down[childs[v][md]] <= down[r]){ le = md; } else { ri = md; } } return from[childs[v][le]]; } }; int n = g.size(); std::vector<E> from(n, e), to(n, e); std::vector<V> dp_to(n); std::vector<std::vector<int>> childs(n); std::vector<int> down(n), up(n); int t = 0; auto dfs = [&](auto sfs, int v, int f) -> void { down[v] = t++; childs[v].reserve(g[v].size()); for (auto [c, eid] : g[v]){ if (c == f) continue; childs[v].emplace_back(c); sfs(sfs, c, v); dp_to[c] = put_vertex(to[c], c); to[c] = put_edge(dp_to[c], eid); to[v] = op(to[v], to[c]); } up[v] = t; }; dfs(dfs, root, -1); std::vector<V> dp_ans(n), dp_from(n); std::vector<E> inner(n); auto bfs = [&](auto sfs, int v, int f) -> void { int sz = g[v].size(); inner[sz] = e; int i = sz-1; for (auto [c, eid] : g[v] | std::views::reverse){ if (c == f) continue; inner[i] = op(inner[i+1], to[c]); i--; } dp_ans[v] = put_vertex(op(inner[++i], from[v]), v); E rui = e; for (auto [c, eid] : g[v]){ if (c == f) continue; dp_from[c] = put_vertex(op(op(rui, inner[++i]), from[v]), v); from[c] = put_edge(dp_from[c], ~eid); rui = op(rui, to[c]); } for (auto [c, eid] : g[v]){ if (c == f) continue; sfs(sfs, c, v); } }; bfs(bfs, root, -1); return dp{dp_ans, dp_from, dp_to, down, up, childs}; } } // namespace noya2 #line 4 "c.cpp" void solve(){ int n; in(n); vector<vector<pii>> g(n); rep(i,n-1){ int u, v; in(u,v); u--, v--; g[u].emplace_back(v,i); g[v].emplace_back(u,~i); } auto op = [](int a, int b){ return max(a,b); }; auto pute = [](int a, int){ return a+1; }; auto putv = [](int a, int){ return a; }; auto dp = rerootingdp<int,int>(op,0,pute,putv,g); int ans = 1; rep(v,n){ vector<int> adj; for (auto [u, e] : g[v]){ adj.emplace_back(dp(v,u)+1); } sort(all(adj)); reverse(all(adj)); for (int c = 0; auto d : adj){ c++; chmax(ans,c*d+1); } } out(ans); } int main(){ int t = 1; //in(t); while (t--) { solve(); } }