#596718 (C++17(gcc12)) No.1326 ふたりのDominator

• 問題: No.1326 ふたりのDominator
• ユーザー: minato
• 提出日時: 2020-12-23 02:03:33
• 言語: C++17(gcc12) (gcc 12.3.0 + boost 1.87.0)
• 結果: AC
• 実行時間: 174 ms / 2,000 ms
• コード長: 13,858 bytes
• コンパイル時間: 16,499 ms
• コンパイル使用メモリ: 310,552 KB
• 最終ジャッジ日時: 2025-01-17 06:20:47
• ジャッジサーバーID （参考情報）: judge2 / judge5

ファイルパターン	結果
sample	AC * 1
other	AC * 24

ソースコード

#ifdef ONLINE_JUDGE
#pragma GCC target("avx2,avx")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#endif
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ull = unsigned long long;
using i128 = __int128_t;
using pii = pair<int, int>;
using pll = pair<long long, long long>;
template<class T> using vec = vector<T>;
template<class T> using vvec = vector<vector<T>>;
#define rep(i, n) for (int i = 0; i < (n); i++)
#define rrep(i, n) for (int i = int(n) - 1; i >= 0; i--)
#define all(x) (x).begin(), (x).end()
constexpr char ln = '\n';
istream& operator>>(istream& is, __int128_t& x) {
    x = 0;
    string s;
    is >> s;
    int n = int(s.size()), it = 0;
    if (s[0] == '-') it++;
    for (; it < n; it++) x = (x * 10 + s[it] - '0');
    if (s[0] == '-') x = -x;
    return is;
}
ostream& operator<<(ostream& os, __int128_t x) {
    if (x == 0) return os << 0;
    if (x < 0) os << '-', x = -x;
    deque<int> deq;
    while (x) deq.emplace_front(x % 10), x /= 10;
    for (int e : deq) os << e;
    return os;
}
template<class T1, class T2>
ostream& operator<<(ostream& os, const pair<T1, T2>& p) {
    return os << "(" << p.first << ", " << p.second << ")";
}
template<class T> 
ostream& operator<<(ostream& os, const vector<T>& v) {
    os << "{";
    for (int i = 0; i < int(v.size()); i++) {
        if (i) os << ", ";
        os << v[i];
    }
    return os << "}";
}
template<class Container> inline int SZ(Container& v) { return int(v.size()); }
template<class T> inline void UNIQUE(vector<T>& v) { v.erase(unique(v.begin(), v.end()), v.end()); }
template<class T1, class T2> inline bool chmax(T1& a, T2 b) { if (a < b) {a = b; return true ;} return false ;}
template<class T1, class T2> inline bool chmin(T1& a, T2 b) { if (a > b) {a = b; return true ;} return false ;}
inline int topbit(ull x) { return x == 0 ? -1 : 63 - __builtin_clzll(x); }
inline int botbit(ull x) { return x == 0 ? 64 : __builtin_ctzll(x); }
inline int popcount(ull x) { return __builtin_popcountll(x); }
inline int kthbit(ull x, int k) { return (x>>k) & 1; }
inline constexpr long long TEN(int x) { return x == 0 ? 1 : TEN(x-1) * 10; }
inline void print() { cout << "\n"; }
template<class T>
inline void print(const vector<T>& v) {
    for (int i = 0; i < int(v.size()); i++) {
        if (i) cout << " ";
        cout << v[i];
    }
    print();
}
template<class T, class... Args>
inline void print(const T& x, const Args& ... args) {
    cout << x << " ";
    print(args...);
}
#ifdef MINATO_LOCAL
inline void debug_out() { cerr << endl; }
template <class T, class... Args>
inline void debug_out(const T& x, const Args& ... args) {
    cerr << " " << x;
    debug_out(args...);
}
#define debug(...) cerr << __LINE__ << " : [" << #__VA_ARGS__ << "] =", debug_out(__VA_ARGS__)
#define dump(x) cerr << __LINE__ << " : " << #x << " = " << (x) << endl
#else
#define debug(...) (void(0))
#define dump(x) (void(0))
#endif
struct fast_ios { fast_ios() { cin.tie(nullptr); ios::sync_with_stdio(false); cout << fixed << setprecision(20); }; } fast_ios_;
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

struct UnionFind {
    int N;
    vector<int> node;

    UnionFind(){}
    UnionFind(int N) : N(N), node(N,-1) {}

    void init(int x) {
        node.assign(x,-1);
        N = x;
    }

    bool merge(int x, int y) {
        x = root(x); y = root(y);
        if (x == y) return false;
        if (node[x] > node[y]) swap(x,y);
        node[x] += node[y];
        node[y] = x;
        N--;
        return true; 
    }

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

    int root(int x) {
        if (node[x] < 0) return x;
        return node[x] = root(node[x]);
    }

    int size(int x) {return -node[root(x)];}

    int count() const {return N;}
};
template<typename T>
struct BinaryIndexedTree {
    int N;
    vector<T> data;

    BinaryIndexedTree(){}
    BinaryIndexedTree(int N) : N(N), data(N+1,0) {}

    // [0,k) (0-indexed) a[0] + … + a[k-1]
    T sum(int k) {
        T ret = 0;
        for(; k > 0; k -= k & -k) ret += data[k];
        return ret;
    }

    // [l,r) (0-indexed) a[l] + …　+ a[r-1]
    T sum(int l, int r) {
        if (l >= r) return 0;
        T vl = sum(l);
        T vr = sum(r);
        return vr - vl;
    }
    // (0-indexed) a[k] += x;
    void add(int k, T x) {
        for(++k; k <= N; k += k & -k) data[k] += x;
    }

    // (0-indexed)
    int lowerbound(T x) {
        int k = 1;
        int ret = 0;
        while ((k<<1) <= N) k <<= 1;
        while (k) {
            if (ret + k <= N && data[ret+k] < x) {
                x -= data[ret+k];
                ret += k;
            }
            k >>= 1;
        }
        return ret;
    }

    // (0-indexed)
    int upperbound(T x) {return lowerbound(x+1);}
};

/*
    辺は2つの頂点のうち深い方の頂点に対応させる(根は対応させない)
    !!辺クエリでも確保するセグ木の長さはN!(根に対応する添え字0だけ使わない)

    部分木クエリ 計算量 O(α) (セグ木ならO(logN))
    部分木頂点クエリ
    seg.get(hld.vid[v],hld.vid[v]+hld.sub[v]);
    部分木辺クエリ
    seg.get(hld.vid[v]+1,hld.vid[v]+hld.sub[v]);

    auto f=[&](int l, int r) {
        //区間[l,r)に対する処理
    };
*/
struct HeavyLightDecomposition {
    vector<vector<int>> G;
    vector<int> vid, head, sub, par, dep, inv, type;

    HeavyLightDecomposition(int N) :
        G(N),vid(N,-1),head(N),sub(N,1),
        par(N,-1),dep(N,0),inv(N),type(N){}

    void add_edge(int u,int v) {
        G[u].emplace_back(v);
        G[v].emplace_back(u);
    }

    void build(vector<int> rs = {0}) {
        int c = 0, pos = 0;
        for(int r : rs) {
            dfs_sz(r);
            head[r] = r;
            dfs_hld(r, c++, pos);
        }
    }

    void dfs_sz(int v) {
        for(int& u : G[v]) if(u==par[v]) swap(u,G[v].back());
        if(~par[v]) G[v].pop_back();
        for (int& u : G[v]) {
            par[u] = v;
            dep[u] = dep[v]+1;
            dfs_sz(u);
            sub[v] += sub[u];
            if(sub[u] > sub[G[v][0]]) swap(u,G[v][0]);
        }
    }

    void dfs_hld(int v, int c, int& pos) {
        vid[v] = pos++;
        inv[vid[v]] = v;
        type[v] = c;
        for(int u : G[v]) {
            if(u == par[v]) continue;
            head[u] = (u == G[v][0] ? head[v] : u);
            dfs_hld(u,c,pos);
        }
    }

    int lca(int u, int v) {
        while(true) {
            if(vid[u] > vid[v]) swap(u,v);
            if(head[u] == head[v]) return u;
            v = par[head[v]];
        }
    }

    int distance(int u, int v) {
        return dep[u] + dep[v] - 2*dep[lca(u,v)];
    }

    // for_each(vertex)
    template<class F>
    void for_each(int u, int v, const F& f) {
        while(true) {
            if(vid[u] > vid[v]) swap(u,v);
            f(max(vid[head[v]],vid[u]), vid[v]+1);
            if(head[u] != head[v]) v = par[head[v]];
            else break;
        }
    }

    template<class T, class Q, class F>
    T for_each(int u, int v, T ti, const Q& q, const F& f) {
        T l = ti, r = ti;
        while(true) {
            if(vid[u] > vid[v]) {
                swap(u,v);
                swap(l,r);
            }
            l = f(l, q(max(vid[head[v]],vid[u]), vid[v]+1));
            if(head[u] != head[v]) v = par[head[v]];
            else break;
        }
        return f(l,r);
    }

    // for_each(edge)
    // [l, r) <- attention!!
    template<class F>
    void for_each_edge(int u, int v, const F& f) {
        while(true) {
            if (vid[u] > vid[v]) swap(u,v);
            if (head[u] != head[v]) {
                f(vid[head[v]],vid[v]+1);
                v = par[head[v]];
            } else {
                if (u != v) f(vid[u]+1, vid[v]+1);
                break;
            }
        }
    }

    int search(int v, int d) {
        if (dep[v] < d || d < 0) return -1;
        while (true) {
            if (dep[v] - dep[head[v]] + 1 <= d) {
                d -= dep[v] - dep[head[v]] + 1;
                v = par[head[v]];
            } else {
                return inv[vid[v]-d];
            }
        }
    }
};

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);
    }
  }
};

template< typename T = int >
using Edges = vector< Edge< T > >;


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);
    }
  }

  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;
    for(auto &to : g[idx]) {
      if(to == par && !exchange(beet, true)) {
        continue;
      }
      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) articulation.push_back(idx);
    return k;
  }
};

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 < 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;
          }
        }
      }
    }
  }
};

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);
    }
  }
};

int main() {  
    int N,M; cin >> N >> M;
    BlockCutTree<> BCT(N);
    BCT.read(M);
    BCT.build();
    int K = BCT.tree.size();
    HeavyLightDecomposition HLD(K);
    UnionFind uf(K);
    rep(i,K) {
        for (auto& e : BCT.tree.g[i]) {
            if (uf.merge(e.from,e.to)) {
                HLD.add_edge(e.from,e.to);
            }
        }
    }
    HLD.build();
    BinaryIndexedTree<int> BIT(K);
    for (auto v : BCT.articulation) {
        BIT.add(HLD.vid[BCT[v]],1);
    }

    int Q; cin >> Q;
    while (Q--) {
        int x,y; cin >> x >> y;
        x--; y--;
        int u = BCT[x], v = BCT[y];
        if (u==v) {
            cout << 0 << ln;
            continue;
        }
        int ans = 0;
        auto f=[&](int l, int r) {
            ans += BIT.sum(l,r);
            return;
        };
        HLD.for_each(u,v,f);
        ans -= BIT.sum(HLD.vid[u],HLD.vid[u]+1);
        ans -= BIT.sum(HLD.vid[v],HLD.vid[v]+1);

        cout << ans << ln;
    }
}