This documentation is automatically generated by online-judge-tools/verification-helper
View the Project on GitHub ei1333/library
#define PROBLEM "http://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=GRL_5_C" #include "../../template/template.hpp" #include "../../graph/tree/heavy-light-decomposition.hpp" int main() { int N, Q; cin >> N; HeavyLightDecomposition< int > hld(N); for(int i = 0; i < N; i++) { int k; cin >> k; for(int j = 0; j < k; j++) { int c; cin >> c; hld.add_edge(i, c); } } hld.build(); cin >> Q; for(int i = 0; i < Q; i++) { int u, v; cin >> u >> v; cout << hld.lca(u, v) << "\n"; } }
#line 1 "test/verify/aoj-grl-5-c-2.test.cpp" #define PROBLEM "http://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=GRL_5_C" #line 1 "template/template.hpp" #include<bits/stdc++.h> using namespace std; using int64 = long long; const int mod = 1e9 + 7; const int64 infll = (1LL << 62) - 1; const int inf = (1 << 30) - 1; struct IoSetup { IoSetup() { cin.tie(nullptr); ios::sync_with_stdio(false); cout << fixed << setprecision(10); cerr << fixed << setprecision(10); } } iosetup; template< typename T1, typename T2 > ostream &operator<<(ostream &os, const pair< T1, T2 >& p) { os << p.first << " " << p.second; return os; } template< typename T1, typename T2 > istream &operator>>(istream &is, pair< T1, T2 > &p) { is >> p.first >> p.second; return is; } template< typename T > ostream &operator<<(ostream &os, const vector< T > &v) { for(int i = 0; i < (int) v.size(); i++) { os << v[i] << (i + 1 != v.size() ? " " : ""); } return os; } template< typename T > istream &operator>>(istream &is, vector< T > &v) { for(T &in : v) is >> in; return is; } template< typename T1, typename T2 > inline bool chmax(T1 &a, T2 b) { return a < b && (a = b, true); } template< typename T1, typename T2 > inline bool chmin(T1 &a, T2 b) { return a > b && (a = b, true); } template< typename T = int64 > vector< T > make_v(size_t a) { return vector< T >(a); } template< typename T, typename... Ts > auto make_v(size_t a, Ts... ts) { return vector< decltype(make_v< T >(ts...)) >(a, make_v< T >(ts...)); } template< typename T, typename V > typename enable_if< is_class< T >::value == 0 >::type fill_v(T &t, const V &v) { t = v; } template< typename T, typename V > typename enable_if< is_class< T >::value != 0 >::type fill_v(T &t, const V &v) { for(auto &e : t) fill_v(e, v); } template< typename F > struct FixPoint : F { explicit FixPoint(F &&f) : F(forward< F >(f)) {} template< typename... Args > decltype(auto) operator()(Args &&... args) const { return F::operator()(*this, forward< Args >(args)...); } }; template< typename F > inline decltype(auto) MFP(F &&f) { return FixPoint< F >{forward< F >(f)}; } #line 4 "test/verify/aoj-grl-5-c-2.test.cpp" #line 2 "graph/tree/heavy-light-decomposition.hpp" #line 2 "graph/graph-template.hpp" /** * @brief Graph Template(グラフテンプレート) */ template< typename T = int > struct Edge { int from, to; T cost; int idx; Edge() = default; Edge(int from, int to, T cost = 1, int idx = -1) : from(from), to(to), cost(cost), idx(idx) {} operator int() const { return to; } }; template< typename T = int > struct Graph { vector< vector< Edge< T > > > g; int es; Graph() = default; explicit Graph(int n) : g(n), es(0) {} size_t size() const { return g.size(); } void add_directed_edge(int from, int to, T cost = 1) { g[from].emplace_back(from, to, cost, es++); } void add_edge(int from, int to, T cost = 1) { g[from].emplace_back(from, to, cost, es); g[to].emplace_back(to, from, cost, es++); } void read(int M, int padding = -1, bool weighted = false, bool directed = false) { for(int i = 0; i < M; i++) { int a, b; cin >> a >> b; a += padding; b += padding; T c = T(1); if(weighted) cin >> c; if(directed) add_directed_edge(a, b, c); else add_edge(a, b, c); } } inline vector< Edge< T > > &operator[](const int &k) { return g[k]; } inline const vector< Edge< T > > &operator[](const int &k) const { return g[k]; } }; template< typename T = int > using Edges = vector< Edge< T > >; #line 4 "graph/tree/heavy-light-decomposition.hpp" /** * @brief Heavy-Light-Decomposition(HL分解) * @see https://smijake3.hatenablog.com/entry/2019/09/15/200200 */ template< typename T = int > struct HeavyLightDecomposition : Graph< T > { public: using Graph< T >::Graph; using Graph< T >::g; vector< int > sz, in, out, head, rev, par, dep; void build() { sz.assign(g.size(), 0); in.assign(g.size(), 0); out.assign(g.size(), 0); head.assign(g.size(), 0); rev.assign(g.size(), 0); par.assign(g.size(), 0); dep.assign(g.size(), 0); dfs_sz(0, -1, 0); int t = 0; dfs_hld(0, -1, t); } /* k: 0-indexed */ int la(int v, int k) { while(1) { int u = head[v]; if(in[v] - k >= in[u]) return rev[in[v] - k]; k -= in[v] - in[u] + 1; v = par[u]; } } int lca(int u, int v) const { for(;; v = par[head[v]]) { if(in[u] > in[v]) swap(u, v); if(head[u] == head[v]) return u; } } int dist(int u, int v) const { return dep[u] + dep[v] - 2 * dep[lca(u, v)]; } template< typename E, typename Q, typename F, typename S > E query(int u, int v, const E &ti, const Q &q, const F &f, const S &s, bool edge = false) { E l = ti, r = ti; for(;; v = par[head[v]]) { if(in[u] > in[v]) swap(u, v), swap(l, r); if(head[u] == head[v]) break; l = f(q(in[head[v]], in[v] + 1), l); } return s(f(q(in[u] + edge, in[v] + 1), l), r); } template< typename E, typename Q, typename F > E query(int u, int v, const E &ti, const Q &q, const F &f, bool edge = false) { return query(u, v, ti, q, f, f, edge); } template< typename Q > void add(int u, int v, const Q &q, bool edge = false) { for(;; v = par[head[v]]) { if(in[u] > in[v]) swap(u, v); if(head[u] == head[v]) break; q(in[head[v]], in[v] + 1); } q(in[u] + edge, in[v] + 1); } /* {parent, child} */ vector< pair< int, int > > compress(vector< int > &remark) { auto cmp = [&](int a, int b) { return in[a] < in[b]; }; sort(begin(remark), end(remark), cmp); remark.erase(unique(begin(remark), end(remark)), end(remark)); int K = (int) remark.size(); for(int k = 1; k < K; k++) remark.emplace_back(lca(remark[k - 1], remark[k])); sort(begin(remark), end(remark), cmp); remark.erase(unique(begin(remark), end(remark)), end(remark)); vector< pair< int, int > > es; stack< int > st; for(auto &k : remark) { while(!st.empty() && out[st.top()] <= in[k]) st.pop(); if(!st.empty()) es.emplace_back(st.top(), k); st.emplace(k); } return es; } explicit HeavyLightDecomposition(const Graph< T > &g) : Graph< T >(g) {} private: void dfs_sz(int idx, int p, int d) { dep[idx] = d; par[idx] = p; sz[idx] = 1; if(g[idx].size() && g[idx][0] == p) swap(g[idx][0], g[idx].back()); for(auto &to : g[idx]) { if(to == p) continue; dfs_sz(to, idx, d + 1); sz[idx] += sz[to]; if(sz[g[idx][0]] < sz[to]) swap(g[idx][0], to); } } void dfs_hld(int idx, int p, int ×) { in[idx] = times++; rev[in[idx]] = idx; for(auto &to : g[idx]) { if(to == p) continue; head[to] = (g[idx][0] == to ? head[idx] : to); dfs_hld(to, idx, times); } out[idx] = times; } }; #line 6 "test/verify/aoj-grl-5-c-2.test.cpp" int main() { int N, Q; cin >> N; HeavyLightDecomposition< int > hld(N); for(int i = 0; i < N; i++) { int k; cin >> k; for(int j = 0; j < k; j++) { int c; cin >> c; hld.add_edge(i, c); } } hld.build(); cin >> Q; for(int i = 0; i < Q; i++) { int u, v; cin >> u >> v; cout << hld.lca(u, v) << "\n"; } }