test/verify/yosupo-tree-diameter.test.cpp

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• Last update: 2024-05-01 23:44:47+09:00
• Problem: https://judge.yosupo.jp/problem/tree_diameter

Depends on

• Graph Template(グラフテンプレート) (graph/graph-template.hpp)
• Tree-Diameter(木の直径) (graph/tree/tree-diameter.hpp)
• template/template.hpp

Code

// competitive-verifier: PROBLEM https://judge.yosupo.jp/problem/tree_diameter

#include "../../template/template.hpp"

#include "../../graph/tree/tree-diameter.hpp"

int main() {
  int N;
  cin >> N;
  TreeDiameter< int64_t > g(N);
  g.read(N - 1, 0, true);
  cout << g.build() << " ";
  cout << g.path.size() + 1 << "\n";
  cout << g.path[0].from << " " << g.path << "\n";
}

#line 1 "test/verify/yosupo-tree-diameter.test.cpp"
// competitive-verifier: PROBLEM https://judge.yosupo.jp/problem/tree_diameter

#line 1 "template/template.hpp"
#include <bits/stdc++.h>

using namespace std;

using int64 = long long;

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/yosupo-tree-diameter.test.cpp"

#line 2 "graph/tree/tree-diameter.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/tree-diameter.hpp"

/**
 * @brief Tree-Diameter(木の直径)
 *
 */
template <typename T = int>
struct TreeDiameter : Graph<T> {
 public:
  using Graph<T>::Graph;
  using Graph<T>::g;
  vector<Edge<T> > path;

  T build() {
    to.assign(g.size(), -1);
    auto p = dfs(0, -1);
    auto q = dfs(p.second, -1);

    int now = p.second;
    while (now != q.second) {
      for (auto &e : g[now]) {
        if (to[now] == e.to) {
          path.emplace_back(e);
        }
      }
      now = to[now];
    }
    return q.first;
  }

  explicit TreeDiameter(const Graph<T> &g) : Graph<T>(g) {}

 private:
  vector<int> to;

  pair<T, int> dfs(int idx, int par) {
    pair<T, int> ret(0, idx);
    for (auto &e : g[idx]) {
      if (e.to == par) continue;
      auto cost = dfs(e.to, idx);
      cost.first += e.cost;
      if (ret < cost) {
        ret = cost;
        to[idx] = e.to;
      }
    }
    return ret;
  }
};
#line 6 "test/verify/yosupo-tree-diameter.test.cpp"

int main() {
  int N;
  cin >> N;
  TreeDiameter< int64_t > g(N);
  g.read(N - 1, 0, true);
  cout << g.build() << " ";
  cout << g.path.size() + 1 << "\n";
  cout << g.path[0].from << " " << g.path << "\n";
}

Test cases

Env	Name	Status	Elapsed	Memory
g++	example_00	AC	6 ms	4 MB
g++	hack_00	AC	6 ms	4 MB
g++	line_00	AC	406 ms	85 MB
g++	max_random_00	AC	315 ms	50 MB
g++	max_random_01	AC	334 ms	50 MB
g++	random_00	AC	226 ms	39 MB
g++	random_01	AC	288 ms	46 MB
g++	random_02	AC	25 ms	8 MB
g++	random_03	AC	258 ms	43 MB
g++	random_04	AC	138 ms	29 MB
g++	small_random_00	AC	7 ms	4 MB
g++	small_random_01	AC	6 ms	4 MB
g++	small_random_02	AC	6 ms	4 MB
g++	small_random_03	AC	6 ms	4 MB
g++	small_random_04	AC	6 ms	4 MB
g++	uni_00	AC	164 ms	44 MB
clang++	example_00	AC	6 ms	4 MB
clang++	hack_00	AC	6 ms	4 MB
clang++	line_00	AC	424 ms	102 MB
clang++	max_random_00	AC	316 ms	50 MB
clang++	max_random_01	AC	308 ms	50 MB
clang++	random_00	AC	211 ms	39 MB
clang++	random_01	AC	273 ms	46 MB
clang++	random_02	AC	27 ms	8 MB
clang++	random_03	AC	254 ms	43 MB
clang++	random_04	AC	135 ms	29 MB
clang++	small_random_00	AC	7 ms	4 MB
clang++	small_random_01	AC	6 ms	4 MB
clang++	small_random_02	AC	6 ms	4 MB
clang++	small_random_03	AC	6 ms	4 MB
clang++	small_random_04	AC	6 ms	4 MB
clang++	uni_00	AC	160 ms	45 MB

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