結果

問題 No.1983 [Cherry 4th Tune C] 南の島のマーメイド
コンテスト
ユーザー hitonanode
提出日時 2022-06-17 21:45:05
言語 C++23
(gcc 13.3.0 + boost 1.87.0)
結果
AC  
実行時間 228 ms / 4,000 ms
コード長 11,377 bytes
コンパイル時間 2,296 ms
コンパイル使用メモリ 186,004 KB
実行使用メモリ 40,460 KB
最終ジャッジ日時 2024-10-09 07:24:20
合計ジャッジ時間 9,549 ms
ジャッジサーバーID
（参考情報） 		judge3 / judge2
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 * 41
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 <algorithm>
#include <array>
#include <bitset>
#include <cassert>
#include <chrono>
#include <cmath>
#include <complex>
#include <deque>
#include <forward_list>
#include <fstream>
#include <functional>
#include <iomanip>
#include <ios>
#include <iostream>
#include <limits>
#include <list>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <tuple>
#include <type_traits>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>
using namespace std;
using lint = long long;
using pint = pair<int, int>;
using plint = pair<lint, lint>;
struct fast_ios { fast_ios(){ cin.tie(nullptr), ios::sync_with_stdio(false), cout << fixed << setprecision(20); }; } fast_ios_;
#define ALL(x) (x).begin(), (x).end()
#define FOR(i, begin, end) for(int i=(begin),i##_end_=(end);i<i##_end_;i++)
#define IFOR(i, begin, end) for(int i=(end)-1,i##_begin_=(begin);i>=i##_begin_;i--)
#define REP(i, n) FOR(i,0,n)
#define IREP(i, n) IFOR(i,0,n)
template <typename T, typename V>
void ndarray(vector<T>& vec, const V& val, int len) { vec.assign(len, val); }
template <typename T, typename V, typename... Args> void ndarray(vector<T>& vec, const V& val, int len, Args... args) { vec.resize(len), for_each(begin(vec), end(vec), [&](T& v) { ndarray(v, val, args...); }); }
template <typename T> bool chmax(T &m, const T q) { return m < q ? (m = q, true) : false; }
template <typename T> bool chmin(T &m, const T q) { return m > q ? (m = q, true) : false; }
int floor_lg(long long x) { return x <= 0 ? -1 : 63 - __builtin_clzll(x); }
template <typename T1, typename T2> pair<T1, T2> operator+(const pair<T1, T2> &l, const pair<T1, T2> &r) { return make_pair(l.first + r.first, l.second + r.second); }
template <typename T1, typename T2> pair<T1, T2> operator-(const pair<T1, T2> &l, const pair<T1, T2> &r) { return make_pair(l.first - r.first, l.second - r.second); }
template <typename T> vector<T> sort_unique(vector<T> vec) { sort(vec.begin(), vec.end()), vec.erase(unique(vec.begin(), vec.end()), vec.end()); return vec; }
template <typename T> int arglb(const std::vector<T> &v, const T &x) { return std::distance(v.begin(), std::lower_bound(v.begin(), v.end(), x)); }
template <typename T> int argub(const std::vector<T> &v, const T &x) { return std::distance(v.begin(), std::upper_bound(v.begin(), v.end(), x)); }
template <typename T> istream &operator>>(istream &is, vector<T> &vec) { for (auto &v : vec) is >> v; return is; }
template <typename T> ostream &operator<<(ostream &os, const vector<T> &vec) { os << '['; for (auto v : vec) os << v << ','; os << ']'; return os; }
template <typename T, size_t sz> ostream &operator<<(ostream &os, const array<T, sz> &arr) { os << '['; for (auto v : arr) os << v << ','; os << ']'; return os; }
#if __cplusplus >= 201703L
template <typename... T> istream &operator>>(istream &is, tuple<T...> &tpl) { std::apply([&is](auto &&... args) { ((is >> args), ...);}, tpl); return is; }
template <typename... T> ostream &operator<<(ostream &os, const tuple<T...> &tpl) { os << '('; std::apply([&os](auto &&... args) { ((os << args << ','), ...);}, tpl); return os << ')'; }
#endif
template <typename T> ostream &operator<<(ostream &os, const deque<T> &vec) { os << "deq["; for (auto v : vec) os << v << ','; os << ']'; return os; }
template <typename T> ostream &operator<<(ostream &os, const set<T> &vec) { os << '{'; for (auto v : vec) os << v << ','; os << '}'; return os; }
template <typename T, typename TH> ostream &operator<<(ostream &os, const unordered_set<T, TH> &vec) { os << '{'; for (auto v : vec) os << v << ','; os << '}'; return os; }
template <typename T> ostream &operator<<(ostream &os, const multiset<T> &vec) { os << '{'; for (auto v : vec) os << v << ','; os << '}'; return os; }
template <typename T> ostream &operator<<(ostream &os, const unordered_multiset<T> &vec) { os << '{'; for (auto v : vec) os << v << ','; os << '}'; return os; }
template <typename T1, typename T2> ostream &operator<<(ostream &os, const pair<T1, T2> &pa) { os << '(' << pa.first << ',' << pa.second << ')'; return os; }
template <typename TK, typename TV> ostream &operator<<(ostream &os, const map<TK, TV> &mp) { os << '{'; for (auto v : mp) os << v.first << "=>" << v.second << ','; os << '}'; return os; }
template <typename TK, typename TV, typename TH> ostream &operator<<(ostream &os, const unordered_map<TK, TV, TH> &mp) { os << '{'; for (auto v : mp) os << v.first << "=>" << v.second << ','; os << '}'; return os; }
#ifdef HITONANODE_LOCAL
const string COLOR_RESET = "\033[0m", BRIGHT_GREEN = "\033[1;32m", BRIGHT_RED = "\033[1;31m", BRIGHT_CYAN = "\033[1;36m", NORMAL_CROSSED = "\033[0;9;37m", RED_BACKGROUND = "\033[1;41m", NORMAL_FAINT = "\033[0;2m";
#define dbg(x) cerr << BRIGHT_CYAN << #x << COLOR_RESET << " = " << (x) << NORMAL_FAINT << " (L" << __LINE__ << ") " << __FILE__ << COLOR_RESET << endl
#define dbgif(cond, x) ((cond) ? cerr << BRIGHT_CYAN << #x << COLOR_RESET << " = " << (x) << NORMAL_FAINT << " (L" << __LINE__ << ") " << __FILE__ << COLOR_RESET << endl : cerr)
#else
#define dbg(x) 0
#define dbgif(cond, x) 0
#endif

#include <algorithm>
#include <cassert>
#include <queue>
#include <utility>
#include <vector>

struct lowlink {
    int V; // # of vertices
    int E; // # of edges
    int k;
    std::vector<std::vector<std::pair<int, int>>> to;
    std::vector<std::pair<int, int>> edges;
    std::vector<int> root_ids; // DFS forestの構築で根になった頂点

    std::vector<int> is_bridge;       // Whether edge i is bridge or not, size = E
    std::vector<int> is_articulation; // whether vertex i is articulation point or not, size = V

    // lowlink
    std::vector<int> order;           // visiting order of DFS tree, size = V
    std::vector<int> lowlink_;        // size = V
    std::vector<int> is_dfstree_edge; // size = E

    int tecc_num;             // 二重辺連結成分数
    std::vector<int> tecc_id; // 各頂点が何個目の二重辺連結成分か

    int tvcc_num;             // 二重頂点連結成分数
    std::vector<int> tvcc_id; // 各辺が何個目の二重頂点連結成分か

    lowlink(int V)
        : V(V), E(0), k(0), to(V), is_articulation(V, 0), order(V, -1), lowlink_(V, -1),
          tecc_num(0), tvcc_num(0) {}

    void add_edge(int v1, int v2) {
        assert(v1 >= 0 and v1 < V);
        assert(v2 >= 0 and v2 < V);
        to[v1].emplace_back(v2, E);
        to[v2].emplace_back(v1, E);
        edges.emplace_back(v1, v2);
        is_bridge.push_back(0);
        is_dfstree_edge.push_back(0);
        tvcc_id.push_back(-1);
        E++;
    }

    std::vector<int> _edge_stack;
    int _root_now;

    // Build DFS tree
    // Complexity: O(V + E)
    void dfs_lowlink(int now, int prv_eid = -1) {
        if (prv_eid < 0) _root_now = k;
        if (prv_eid == -1) root_ids.push_back(now);
        order[now] = lowlink_[now] = k++;
        for (const auto &nxt : to[now]) {
            if (nxt.second == prv_eid) continue;
            if (order[nxt.first] < order[now]) _edge_stack.push_back(nxt.second);
            if (order[nxt.first] >= 0) {
                lowlink_[now] = std::min(lowlink_[now], order[nxt.first]);
            } else {
                is_dfstree_edge[nxt.second] = 1;
                dfs_lowlink(nxt.first, nxt.second);
                lowlink_[now] = std::min(lowlink_[now], lowlink_[nxt.first]);

                if ((order[now] == _root_now and order[nxt.first] != _root_now + 1) or
                    (order[now] != _root_now and lowlink_[nxt.first] >= order[now])) {
                    is_articulation[now] = 1;
                }
                if (lowlink_[nxt.first] >= order[now]) {
                    while (true) {
                        int e = _edge_stack.back();
                        tvcc_id[e] = tvcc_num;
                        _edge_stack.pop_back();
                        if (e == nxt.second) break;
                    }
                    tvcc_num++;
                }
            }
        }
    }

    void build() {
        for (int v = 0; v < V; ++v) {
            if (order[v] < 0) dfs_lowlink(v);
        }

        // Find all bridges
        // Complexity: O(V + E)
        for (int i = 0; i < E; i++) {
            int v1 = edges[i].first, v2 = edges[i].second;
            if (order[v1] > order[v2]) std::swap(v1, v2);
            is_bridge[i] = order[v1] < lowlink_[v2];
        }
    }

    // Find two-edge-connected components and classify all vertices
    // Complexity: O(V + E)
    std::vector<std::vector<int>> two_edge_connected_components() {
        build();
        tecc_num = 0;
        tecc_id.assign(V, -1);

        std::vector<int> st;
        for (int i = 0; i < V; i++) {
            if (tecc_id[i] != -1) continue;
            tecc_id[i] = tecc_num;
            st.push_back(i);
            while (!st.empty()) {
                int now = st.back();
                st.pop_back();
                for (const auto &edge : to[now]) {
                    int nxt = edge.first;
                    if (tecc_id[nxt] >= 0 or is_bridge[edge.second]) continue;
                    tecc_id[nxt] = tecc_num;
                    st.push_back(nxt);
                }
            }
            ++tecc_num;
        }
        std::vector<std::vector<int>> ret(tecc_num);
        for (int i = 0; i < V; ++i) ret[tecc_id[i]].push_back(i);
        return ret;
    }

    // Find biconnected components and classify all edges
    // Complexity: O(V + E)
    std::vector<std::vector<int>> biconnected_components() {
        build();
        std::vector<std::vector<int>> ret(tvcc_num);
        for (int i = 0; i < E; ++i) ret[tvcc_id[i]].push_back(i);
        return ret;
    }
};

#include <algorithm>
#include <numeric>
#include <utility>
#include <vector>

// UnionFind Tree (0-indexed), based on size of each disjoint set
struct UnionFind {
    std::vector<int> par, cou;
    UnionFind(int N = 0) : par(N), cou(N, 1) { iota(par.begin(), par.end(), 0); }
    int find(int x) { return (par[x] == x) ? x : (par[x] = find(par[x])); }
    bool unite(int x, int y) {
        x = find(x), y = find(y);
        if (x == y) return false;
        if (cou[x] < cou[y]) std::swap(x, y);
        par[y] = x, cou[x] += cou[y];
        return true;
    }
    int count(int x) { return cou[find(x)]; }
    bool same(int x, int y) { return find(x) == find(y); }
    std::vector<std::vector<int>> groups() {
        std::vector<std::vector<int>> ret(par.size());
        for (int i = 0; i < int(par.size()); ++i) ret[find(i)].push_back(i);
        ret.erase(std::remove_if(ret.begin(), ret.end(),
                                 [&](const std::vector<int> &v) { return v.empty(); }),
                  ret.end());
        return ret;
    }
};


int main() {
    int N, M, Q;
    cin >> N >> M >> Q;
    vector<pint> edges(M);
    lowlink graph(N);
    for (auto &[s, t] : edges) {
        cin >> s >> t;
        --s, --t;
        graph.add_edge(s, t);
    }
    graph.build();
    UnionFind uf(N);
    REP(e, M) {
        if (graph.is_bridge.at(e)) {
            auto [s, t] = edges[e];
            uf.unite(s, t);
        }
    }

    while (Q--) {
        int x, y;
        cin >> x >> y;
        --x, --y;
        cout << (uf.same(x, y) ? "Yes" : "No") << '\n';
    }
}
0