Asa's CP Library

a01sa01to's competitive programming library. Requires C++20 or higher with GCC. This documentation is automatically generated by online-judge-tools/verification-helper

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:heavy_check_mark: tests/graph/eulerian-walk/libchecker-directed.test.cpp

Depends on

Code

#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < (n); ++i)
using ll = long long;
using ull = unsigned long long;

#include "../../../library/fastio.hpp"
#include "../../../library/graph/eulerian-walk.hpp"
#define PROBLEM "https://judge.yosupo.jp/problem/eulerian_trail_directed"

void solve() {
  int n, m;
  asalib::in >> n >> m;
  vector<pair<int, int>> edges(m);
  rep(i, m) {
    int u, v;
    asalib::in >> u >> v;
    edges[i] = { u, v };
  }
  auto res = asalib::graph::eulerian_walk(n, edges, true);
  if (!res.has_value()) {
    asalib::out << "No" << '\n';
  }
  else {
    asalib::out << "Yes" << '\n';
    auto [vs, es] = res.value();
    rep(i, vs.size()) {
      if (i) asalib::out << ' ';
      asalib::out << vs[i];
    }
    asalib::out << '\n';
    rep(i, es.size()) {
      if (i) asalib::out << ' ';
      asalib::out << es[i];
    }
    asalib::out << '\n';
  }
}

int main() {
  int t;
  asalib::in >> t;
  while (t--) solve();
  return 0;
}
#line 1 "tests/graph/eulerian-walk/libchecker-directed.test.cpp"
#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < (n); ++i)
using ll = long long;
using ull = unsigned long long;

#line 2 "library/fastio.hpp"

#line 5 "library/fastio.hpp"
#include <concepts>
#line 11 "library/fastio.hpp"
#include <type_traits>
using namespace std;

// TODO: 何も入力がない場合にも対応する?

namespace asalib {
  namespace _internal {
    class FastIn {
      static constexpr unsigned int BUFFER_SIZE = 1 << 20;
      static constexpr unsigned int MAX_TOKEN_SIZE = 64;
      array<char, BUFFER_SIZE> read_buffer = {};
      array<char, BUFFER_SIZE>::iterator read_ptr = nullptr;
      unsigned int read_size = 0;

      public:
      FastIn() {
        read_buffer.fill(0);
        read_ptr = read_buffer.begin();
        load();
      }

      private:
      void load() {
        // まだ読んでないデータを前に持ってくる
        memcpy(read_buffer.begin(), read_ptr, read_size - (read_ptr - read_buffer.begin()));
        read_size -= read_ptr - read_buffer.begin();
        read_ptr = read_buffer.begin();
        // stdin から読み込み
        read_size += fread(read_buffer.begin() + read_size, 1, BUFFER_SIZE - read_size, stdin);
      }

      void skip_space() {
        // 制御文字 + space
        // DEL (127 = 0x7F) がコーナーケースだがまあ使わんやろ
        while (*read_ptr <= ' ') ++read_ptr;
      }

      template<typename T>
        requires(integral<T> || is_same_v<T, __int128_t> || is_same_v<T, __uint128_t>)
      void _read_uint(T& x) {
        x = 0;
        while (true) {
          uint64_t v;
          memcpy(&v, read_ptr, 8);
          // '0' -> 0 処理
          // こっちを先にやることで制御文字系もはじく
          v -= 0x30'30'30'30'30'30'30'30;
          // ASCII 範囲外
          if (v & 0x80'80'80'80'80'80'80'80) break;
          // 桁ごとの数字から数値に
          v = (v * 10 + (v >> 8)) & 0x00ff00ff00ff00ff;
          v = (v * 100 + (v >> 16)) & 0x0000ffff0000ffff;
          v = (v * 10000 + (v >> 32)) & 0x00000000ffffffff;
          x = 1'0000'0000 * x + v;
          read_ptr += 8;
        }
        while (true) {
          uint32_t v;
          memcpy(&v, read_ptr, 4);
          v -= 0x30'30'30'30;
          if (v & 0x80'80'80'80) break;
          v = (v * 10 + (v >> 8)) & 0x00ff00ff;
          v = (v * 100 + (v >> 16)) & 0x0000ffff;
          x = 1'0000 * x + v;
          read_ptr += 4;
        }
        while (true) {
          uint16_t v;
          memcpy(&v, read_ptr, 2);
          v -= 0x3030;
          if (v & 0x8080) break;
          v = (v * 10 + (v >> 8)) & 0x00ff;
          x = 100 * x + v;
          read_ptr += 2;
        }
        if (*read_ptr > ' ') x = 10 * x + (*read_ptr++ & 0x0f);
      }

      void read_commonop() {
        // そろそろ限界なら読み込み
        if ((read_ptr - read_buffer.begin()) + MAX_TOKEN_SIZE >= BUFFER_SIZE) load();
        skip_space();
      }

      public:
      FastIn& operator>>(char& x) {
        read_commonop();
        x = *read_ptr++;
        return *this;
      }

      FastIn& operator>>(string& x) {
        read_commonop();
        x.clear();
        while (*read_ptr > ' ') {
          x += *read_ptr++;
          if (read_ptr == read_buffer.end()) load();
        }
        return *this;
      }

      template<typename T>
        requires(integral<T> || is_same_v<T, __int128_t> || is_same_v<T, __uint128_t>)
      FastIn& operator>>(T& x) {
        read_commonop();
        if constexpr (is_signed_v<T> || is_same_v<T, __int128_t>) {
          if (*read_ptr == '-') {
            ++read_ptr;
            _read_uint(x);
            x = -x;
            return *this;
          }
        }
        _read_uint(x);
        return *this;
      }
    };

    class FastOut {
      static constexpr unsigned int BUFFER_SIZE = 1 << 20;
      static constexpr unsigned int MAX_TOKEN_SIZE = 64;
      static constexpr unsigned int MAX_PRECOMPUTE_NUM = 1'0000;
      static constexpr unsigned int MAX_PRECOMPUTE_NUM_DIGIT = 4;
      array<char, BUFFER_SIZE> write_buffer = {};
      array<char, BUFFER_SIZE>::iterator write_ptr = nullptr;

      public:
      FastOut() {
        write_buffer.fill(0);
        write_ptr = write_buffer.begin();
      }
      ~FastOut() { flush(); }

      private:
      static constexpr array<char, MAX_PRECOMPUTE_NUM * MAX_PRECOMPUTE_NUM_DIGIT> digits = [] {
        array<char, MAX_PRECOMPUTE_NUM * MAX_PRECOMPUTE_NUM_DIGIT> digits {};
        for (unsigned int i = 0; i < MAX_PRECOMPUTE_NUM; ++i) {
          unsigned int x = i;
          for (int j = MAX_PRECOMPUTE_NUM_DIGIT - 1; j >= 0; --j) {
            digits[i * MAX_PRECOMPUTE_NUM_DIGIT + j] = '0' + (x % 10);
            x /= 10;
          }
        }
        return digits;
      }();

      template<typename T>
        requires(integral<T> || is_same_v<T, __int128_t> || is_same_v<T, __uint128_t>)
      static constexpr array<T, numeric_limits<T>::digits10 + 1> Pow10 = [] {
        array<T, numeric_limits<T>::digits10 + 1> pow10 {};
        pow10[0] = 1;
        for (unsigned int i = 1; i < pow10.size(); ++i) pow10[i] = pow10[i - 1] * 10;
        return pow10;
      }();

      void write_commonop() {
        // そろそろ限界なら書き込む
        if ((write_ptr - write_buffer.begin()) + MAX_TOKEN_SIZE >= BUFFER_SIZE) flush();
      }

      void putchar(const char& x) { *write_ptr++ = x; }

      template<typename T, int NumDig>
        requires(integral<T> || is_same_v<T, __int128_t> || is_same_v<T, __uint128_t>)
      void _write_uint_top(const T& x) {
        // leading-zero を書き込まないようにする
        if constexpr (NumDig > 1) {
          if (x < Pow10<T>[NumDig - 1]) {
            _write_uint_top<T, NumDig - 1>(x);
            return;
          }
        }
        copy_n(digits.begin() + (x + 1) * MAX_PRECOMPUTE_NUM_DIGIT - NumDig, NumDig, write_ptr);
        write_ptr += NumDig;
      }

      template<typename T, int NumDig>
        requires(integral<T> || is_same_v<T, __int128_t> || is_same_v<T, __uint128_t>)
      void _write_uint(const T& x) {
        if constexpr (NumDig >= 0) {
          if constexpr (NumDig > MAX_PRECOMPUTE_NUM_DIGIT) _write_uint<T, NumDig - MAX_PRECOMPUTE_NUM_DIGIT>(x / MAX_PRECOMPUTE_NUM);
          copy_n(digits.begin() + x % MAX_PRECOMPUTE_NUM * MAX_PRECOMPUTE_NUM_DIGIT, MAX_PRECOMPUTE_NUM_DIGIT, write_ptr);
          write_ptr += MAX_PRECOMPUTE_NUM_DIGIT;
        }
      }

      template<typename T, int NumDig>
        requires(integral<T> || is_same_v<T, __int128_t> || is_same_v<T, __uint128_t>)
      void _write_uint_root(const T& x) {
        if constexpr (is_same_v<T, __int128_t> || is_same_v<T, __uint128_t>) {
          // 128bit 除算はおそいので 64bit 除算を使う
          if (x < Pow10<T>[16]) {
            _write_uint_root<uint64_t, NumDig>(x);
          }
          else if (x < Pow10<T>[32]) {
            _write_uint_root<uint64_t, NumDig>(x / Pow10<T>[16]);
            _write_uint<uint64_t, 16>(x % Pow10<T>[16]);
          }
          else {
            _write_uint_root<uint64_t, NumDig>(x / Pow10<T>[32]);
            _write_uint<uint64_t, 16>(x % Pow10<T>[32] / Pow10<T>[16]);
            _write_uint<uint64_t, 16>(x % Pow10<T>[16]);
          }
          return;
        }

        if constexpr (NumDig < numeric_limits<T>::digits10) {
          if (x >= Pow10<T>[NumDig]) {
            _write_uint_root<T, NumDig + MAX_PRECOMPUTE_NUM_DIGIT>(x);
            return;
          }
        }
        _write_uint_top<T, MAX_PRECOMPUTE_NUM_DIGIT>(x / Pow10<T>[NumDig - MAX_PRECOMPUTE_NUM_DIGIT]);
        if constexpr (NumDig > MAX_PRECOMPUTE_NUM_DIGIT) _write_uint<T, NumDig - MAX_PRECOMPUTE_NUM_DIGIT>(x % Pow10<T>[NumDig - MAX_PRECOMPUTE_NUM_DIGIT]);
      }

      public:
      void flush() {
        fwrite(write_buffer.begin(), 1, write_ptr - write_buffer.begin(), stdout);
        write_ptr = write_buffer.begin();
      }

      FastOut& operator<<(const char& x) {
        write_commonop();
        putchar(x);
        return *this;
      }

      FastOut& operator<<(const string& x) {
        write_commonop();
        unsigned int idx = 0;
        while (idx < x.size()) {
          const unsigned int siz = min(BUFFER_SIZE - static_cast<unsigned int>(write_ptr - write_buffer.begin()), static_cast<unsigned int>(x.size()) - idx);
          copy_n(x.begin() + idx, siz, write_ptr);
          write_ptr += siz;
          idx += siz;
          if (write_ptr == write_buffer.end()) flush();
        }
        return *this;
      }

      template<typename T>
        requires(integral<T> || is_same_v<T, __int128_t> || is_same_v<T, __uint128_t>)
      FastOut& operator<<(const T& x) {
        write_commonop();
        if constexpr (is_signed_v<T> || is_same_v<T, __int128_t>) {
          if (x < 0) {
            putchar('-');
            _write_uint_root<T, MAX_PRECOMPUTE_NUM_DIGIT>(-x);
            return *this;
          }
        }
        _write_uint_root<T, MAX_PRECOMPUTE_NUM_DIGIT>(x);
        return *this;
      }
    };
  }  // namespace _internal

  inline _internal::FastIn in;
  inline _internal::FastOut out;
}  // namespace asalib
#line 2 "library/graph/eulerian-walk.hpp"

#line 5 "library/graph/eulerian-walk.hpp"
#include <optional>
#include <ranges>
#line 9 "library/graph/eulerian-walk.hpp"
using namespace std;

#line 2 "library/_internal/graph-base.hpp"

#line 6 "library/_internal/graph-base.hpp"
using namespace std;

namespace asalib::_internal {
  // vector<vector<int>> とかの隣接リストを表す型
  template<class T>
  concept adjacency_list = requires(T t) {
    ranges::ssize(t);
    { t[0] } -> ranges::range;
    { *ranges::begin(t[0]) } -> convertible_to<int>;
  };

  // 辺のリストを表す型
  // 重み付きも考慮し pair<int, int> と tuple<int, int, int> の両方を許容
  template<class T>
  concept edge_list = requires(T t) {
    ranges::ssize(t);
    { get<0>(t[0]) } -> convertible_to<int>;
    { get<1>(t[0]) } -> convertible_to<int>;
  };
}  // namespace asalib::_internal
#line 2 "library/graph/connection.hpp"

#line 4 "library/graph/connection.hpp"
using namespace std;

#line 7 "library/graph/connection.hpp"

namespace asalib::graph {
  template<_internal::adjacency_list T>
  bool is_connected(const T& adj_list) {
    vector<bool> visited(adj_list.size(), false);
    vector<int> st;
    st.reserve(adj_list.size());
    st.emplace_back(0);
    visited[0] = true;
    while (!st.empty()) {
      int v = st.back();
      st.pop_back();
      for (const auto& u : adj_list[v]) {
        if (!visited[u]) {
          visited[u] = true;
          st.emplace_back(u);
        }
      }
    }
    for (const auto v : visited) {
      if (!v) return false;
    }
    return true;
  }
}  // namespace asalib::graph
#line 13 "library/graph/eulerian-walk.hpp"

namespace asalib::graph {
  template<_internal::edge_list T>
  optional<pair<vector<int>, vector<int>>> eulerian_walk(const int n, const T& edgelist, const bool is_directed) {
    constexpr int None = -1;

    // もし辺がなければオイラーグラフ、任意の頂点を返す
    if (edgelist.empty()) [[unlikely]]
      return make_pair(vector<int> { 0 }, vector<int> {});

    // 辺がない頂点を除外したグラフを作成
    int n_vertex_withedge = 0;
    vector<int> id(n, None), indeg(n, 0), outdeg(n, 0);
    for (const auto& p : edgelist) {
      const auto &u = get<0>(p), &v = get<1>(p);
      ++outdeg[u], ++indeg[v];
      if (id[u] == None) id[u] = n_vertex_withedge++;
      if (id[v] == None) id[v] = n_vertex_withedge++;
    }
    vector idrev(n_vertex_withedge, None);
    for (int i = 0; i < n; ++i)
      if (id[i] != None) idrev[id[i]] = i;

    vector Graph(n_vertex_withedge, vector<int>());
    vector underlyingGraph(n_vertex_withedge, vector<int>());
    for (int i = 0; i < n_vertex_withedge; ++i) {
      const int bidir_siz = indeg[idrev[i]] + outdeg[idrev[i]];
      Graph[i].reserve(is_directed ? outdeg[idrev[i]] : bidir_siz);
      underlyingGraph[i].reserve(bidir_siz);
    }
    for (int i = 0; i < ranges::ssize(edgelist); ++i) {
      const auto& p = edgelist[i];
      const auto &u = get<0>(p), &v = get<1>(p);
      Graph[id[u]].emplace_back(i);
      if (!is_directed) Graph[id[v]].emplace_back(i);
      underlyingGraph[id[u]].emplace_back(id[v]);
      underlyingGraph[id[v]].emplace_back(id[u]);
    }

    // 連結でなければ存在しない
    if (!is_connected(underlyingGraph)) return nullopt;

    // オイラーグラフとなるか判定
    int start = None, end = None;
    for (int idx = 0; idx < n_vertex_withedge; ++idx) {
      const int i = idrev[idx];
      if (is_directed) {
        if (indeg[i] == outdeg[i]) continue;
        if (indeg[i] + 1 == outdeg[i]) {
          if (start != None) return nullopt;
          start = idx;
          continue;
        }
        if (indeg[i] == outdeg[i] + 1) {
          if (end != None) return nullopt;
          end = idx;
          continue;
        }
        return nullopt;
      }
      if ((indeg[i] + outdeg[i]) % 2 == 0) continue;
      if (start == None)
        start = idx;
      else if (end == None)
        end = idx;
      else
        return nullopt;
    }
    if ((start == None) xor (end == None)) return nullopt;

    if (start == None) {
      assert(end == None);
      start = end = 0;
    }

    // グラフ探索パート
    vector<bool> used(edgelist.size(), false);
    vector<int> vs, es;
    vector<pair<int, int>> st = { { start, None } };
    vs.reserve(edgelist.size() + 1);
    es.reserve(edgelist.size());
    st.reserve(edgelist.size() + 1);
    while (!st.empty()) {
      auto [v, inedge] = st.back();
      while (!Graph[v].empty() && used[Graph[v].back()]) Graph[v].pop_back();
      if (Graph[v].empty()) {
        st.pop_back();
        vs.emplace_back(v);
        if (inedge != None) es.emplace_back(inedge);
      }
      else {
        const int e = Graph[v].back();
        Graph[v].pop_back();
        used[e] = true;
        const auto& p = edgelist[e];
        const auto &u = get<0>(p), &w = get<1>(p);
        const int to = id[u] == v ? id[w] : id[u];
        st.emplace_back(to, e);
      }
    }

    assert(vs.size() == es.size() + 1);
    assert(es.size() == edgelist.size());

    ranges::reverse(vs);
    ranges::reverse(es);

    // 元の頂点番号に戻す
    vector<int> vs_orig(vs.size());
    for (int i = 0; i < ranges::ssize(vs); ++i) vs_orig[i] = idrev[vs[i]];

    return make_pair(vs_orig, es);
  }
}  // namespace asalib::graph
#line 9 "tests/graph/eulerian-walk/libchecker-directed.test.cpp"
#define PROBLEM "https://judge.yosupo.jp/problem/eulerian_trail_directed"

void solve() {
  int n, m;
  asalib::in >> n >> m;
  vector<pair<int, int>> edges(m);
  rep(i, m) {
    int u, v;
    asalib::in >> u >> v;
    edges[i] = { u, v };
  }
  auto res = asalib::graph::eulerian_walk(n, edges, true);
  if (!res.has_value()) {
    asalib::out << "No" << '\n';
  }
  else {
    asalib::out << "Yes" << '\n';
    auto [vs, es] = res.value();
    rep(i, vs.size()) {
      if (i) asalib::out << ' ';
      asalib::out << vs[i];
    }
    asalib::out << '\n';
    rep(i, es.size()) {
      if (i) asalib::out << ' ';
      asalib::out << es[i];
    }
    asalib::out << '\n';
  }
}

int main() {
  int t;
  asalib::in >> t;
  while (t--) solve();
  return 0;
}
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