結果

問題 No.1983 [Cherry 4th Tune C] 南の島のマーメイド
ユーザー ei1333333ei1333333
提出日時 2022-06-17 22:30:24
言語 C++17
(gcc 13.3.0 + boost 1.87.0)
結果
WA  
実行時間 -
コード長 9,606 bytes
コンパイル時間 4,747 ms
コンパイル使用メモリ 264,976 KB
最終ジャッジ日時 2025-01-29 22:20:57
ジャッジサーバーID
（参考情報） 		judge5 / judge3
このコードへのチャレンジ
（要ログイン）
ファイルパターン 結果
other AC * 14 WA * 27
権限があれば一括ダウンロードができます

ソースコード

diff # 

#include<bits/stdc++.h>
#include<atcoder/all>

using namespace std;

using int64 = long long;
//const int mod = 1e9 + 7;
const int mod = 998244353;

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 {
  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 2 "graph/graph-template.hpp"

#line 2 "graph/others/block-cut-tree.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 2 "graph/others/low-link.hpp"

#line 4 "graph/others/low-link.hpp"

/**
 * @brief Low Link(橋/関節点)
 * @see http://kagamiz.hatenablog.com/entry/2013/10/05/005213
 * @docs docs/low-link.md
 */
template< typename T = int >
struct LowLink : Graph< T > {
public:
  using Graph< T >::Graph;
  vector< int > ord, low, articulation;
  vector< Edge< T > > bridge;
  using Graph< T >::g;

  virtual void build() {
    used.assign(g.size(), 0);
    ord.assign(g.size(), 0);
    low.assign(g.size(), 0);
    int k = 0;
    for(int i = 0; i < (int) g.size(); i++) {
      if(!used[i]) {
        k = dfs(i, k, -1);
        if(g[i].size() == 1) articulation.emplace_back(i);
      }
    }
  }

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

private:
  vector< int > used;

  int dfs(int idx, int k, int par) {
    used[idx] = true;
    ord[idx] = k++;
    low[idx] = ord[idx];
    bool is_articulation = false, beet = false;
    int cnt = 0;
    bool flag = true;
    for(auto &to: g[idx]) {
      if(to == par && !exchange(beet, true)) {
        continue;
      }
      flag = false;
      if(!used[to]) {
        ++cnt;
        k = dfs(to, k, idx);
        low[idx] = min(low[idx], low[to]);
        is_articulation |= par >= 0 && low[to] >= ord[idx];
        if(ord[idx] < low[to]) bridge.emplace_back(to);
      } else {
        low[idx] = min(low[idx], ord[to]);
      }
    }
    is_articulation |= par == -1 && cnt > 1;
    if(is_articulation or flag) articulation.push_back(idx);
    return k;
  }
};

#line 3 "graph/connected-components/bi-connected-components.hpp"

/**
 * @brief Bi Connected Components(二重頂点連結成分分解)
 * @docs docs/bi-connected-components.md
 */
template< typename T = int >
struct BiConnectedComponents : LowLink< T > {
public:
  using LowLink< T >::LowLink;
  using LowLink< T >::g;
  using LowLink< T >::ord;
  using LowLink< T >::low;

  vector< vector< Edge< T > > > bc;

  void build() override {
    LowLink< T >::build();
    used.assign(g.size(), 0);
    for(int i = 0; i < (int) used.size(); i++) {
      if(!used[i]) dfs(i, -1);
    }
  }

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

private:
  vector< int > used;
  vector< Edge< T > > tmp;

  void dfs(int idx, int par) {
    used[idx] = true;
    bool beet = false;
    for(auto &to: g[idx]) {
      if(to == par && !exchange(beet, true)) continue;
      if(!used[to] || ord[to] < ord[idx]) {
        tmp.emplace_back(to);
      }
      if(!used[to]) {
        dfs(to, idx);
        if(low[to] >= ord[idx]) {
          bc.emplace_back();
          for(;;) {
            auto e = tmp.back();
            bc.back().emplace_back(e);
            tmp.pop_back();
            if(e.idx == to.idx) break;
          }
        }
      }
    }
  }
};

#line 5 "graph/others/block-cut-tree.hpp"

/**
 * @brief Block Cut Tree
 * @see https://ei1333.hateblo.jp/entry/2020/03/25/010057
 */
template< typename T = int >
struct BlockCutTree : BiConnectedComponents< T > {
public:
  using BiConnectedComponents< T >::BiConnectedComponents;
  using BiConnectedComponents< T >::g;
  using BiConnectedComponents< T >::articulation;
  using BiConnectedComponents< T >::bc;

  vector< int > rev;
  vector< vector< int > > group;
  Graph< T > tree;

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

  int operator[](const int &k) const {
    return rev[k];
  }

  void build() override {
    BiConnectedComponents< T >::build();
    rev.assign(g.size(), -1);
    int ptr = (int) bc.size();
    for(auto &idx: articulation) {
      rev[idx] = ptr++;
    }
    vector< int > last(ptr, -1);
    tree = Graph< T >(ptr);
    for(int i = 0; i < (int) bc.size(); i++) {
      for(auto &e: bc[i]) {
        for(auto &ver: {e.from, e.to}) {
          if(rev[ver] >= (int) bc.size()) {
            if(exchange(last[rev[ver]], i) != i) {
              tree.add_edge(rev[ver], i, e.cost);
            }
          } else {
            rev[ver] = i;
          }
        }
      }
    }
    group.resize(ptr);
    for(int i = 0; i < (int) g.size(); i++) {
      group[rev[i]].emplace_back(i);
    }
  }
};

/**
 * @brief Union-Find
 * @docs docs/union-find.md
 */
struct UnionFind {
  vector< int > data;

  UnionFind() = default;

  explicit UnionFind(size_t sz) : data(sz, -1) {}

  bool unite(int x, int y) {
    x = find(x), y = find(y);
    if(x == y) return false;
    if(data[x] > data[y]) swap(x, y);
    data[x] += data[y];
    data[y] = x;
    return true;
  }

  int find(int k) {
    if(data[k] < 0) return (k);
    return data[k] = find(data[k]);
  }

  int size(int k) {
    return -data[find(k)];
  }

  bool same(int x, int y) {
    return find(x) == find(y);
  }

  vector< vector< int > > groups() {
    int n = (int) data.size();
    vector< vector< int > > ret(n);
    for(int i = 0; i < n; i++) {
      ret[find(i)].emplace_back(i);
    }
    ret.erase(remove_if(begin(ret), end(ret), [&](const vector< int > &v) {
      return v.empty();
    }));
    return ret;
  }
};

int main() {
  int N, M, Q;
  cin >> N >> M >> Q;
  vector< int > X(M), Y(M);
  vector< int > T(N);
  for(int i = 0; i < M; i++) {
    cin >> X[i] >> Y[i];
    --X[i], --Y[i];
    T[X[i]] = 1;
    T[Y[i]] = 1;
  }
  vector< int > conv(N, -1);
  int R = 0;
  for(int i = 0; i < N; i++) {
    if(T[i]) {
      conv[i] = R++;
    }
  }
  BlockCutTree<> g(R);
  for(int i = 0; i < M; i++) {
    X[i] = conv[X[i]];
    Y[i] = conv[Y[i]];
    g.add_edge(X[i], Y[i]);
  }
  g.build();
  vector< int > ans(Q);
  UnionFind uf(g.tree.size());
  for(int i = g.bc.size(); i < g.tree.size(); i++) {
    if(i >= g.bc.size()) {
      for(auto &j: g.tree[i]) {
        if(g.group[j].empty()) {
          for(auto &k: g.tree[j]) {
            uf.unite(i, k);
          }
        }
      }
    }
  }
  for(int i = 0; i < Q; i++) {
    int x, y;
    cin >> x >> y;
    --x, --y;
    if(~conv[x] and ~conv[y]) {
      x = conv[x];
      y = conv[y];
      x = g[x];
      y = g[y];
      ans[i] = uf.same(x, y);
    }
  }
  for(auto &p: ans) {
    if(p) cout << "Yes\n";
    else cout << "No\n";
  }
}
0