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QOJ

IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#113864#6634. Central SubsetmaspyAC ✓80ms48468kbC++2328.9kb2023-06-19 19:55:382023-06-19 19:55:41

Judging History

你现在查看的是最新测评结果

  • [2023-08-10 23:21:45]
  • System Update: QOJ starts to keep a history of the judgings of all the submissions.
  • [2023-06-19 19:55:41]
  • 评测
  • 测评结果:AC
  • 用时:80ms
  • 内存:48468kb
  • [2023-06-19 19:55:38]
  • 提交

answer

#line 1 "library/my_template.hpp"
#if defined(LOCAL)
#include <my_template_compiled.hpp>
#else
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")

#include <bits/stdc++.h>

using namespace std;

using ll = long long;
using u32 = unsigned int;
using u64 = unsigned long long;
using i128 = __int128;

template <class T>
constexpr T infty = 0;
template <>
constexpr int infty<int> = 1'000'000'000;
template <>
constexpr ll infty<ll> = ll(infty<int>) * infty<int> * 2;
template <>
constexpr u32 infty<u32> = infty<int>;
template <>
constexpr u64 infty<u64> = infty<ll>;
template <>
constexpr i128 infty<i128> = i128(infty<ll>) * infty<ll>;
template <>
constexpr double infty<double> = infty<ll>;
template <>
constexpr long double infty<long double> = infty<ll>;

using pi = pair<ll, ll>;
using vi = vector<ll>;
template <class T>
using vc = vector<T>;
template <class T>
using vvc = vector<vc<T>>;
template <class T>
using vvvc = vector<vvc<T>>;
template <class T>
using vvvvc = vector<vvvc<T>>;
template <class T>
using vvvvvc = vector<vvvvc<T>>;
template <class T>
using pq = priority_queue<T>;
template <class T>
using pqg = priority_queue<T, vector<T>, greater<T>>;

#define vv(type, name, h, ...) \
  vector<vector<type>> name(h, vector<type>(__VA_ARGS__))
#define vvv(type, name, h, w, ...)   \
  vector<vector<vector<type>>> name( \
      h, vector<vector<type>>(w, vector<type>(__VA_ARGS__)))
#define vvvv(type, name, a, b, c, ...)       \
  vector<vector<vector<vector<type>>>> name( \
      a, vector<vector<vector<type>>>(       \
             b, vector<vector<type>>(c, vector<type>(__VA_ARGS__))))

// https://trap.jp/post/1224/
#define FOR1(a) for (ll _ = 0; _ < ll(a); ++_)
#define FOR2(i, a) for (ll i = 0; i < ll(a); ++i)
#define FOR3(i, a, b) for (ll i = a; i < ll(b); ++i)
#define FOR4(i, a, b, c) for (ll i = a; i < ll(b); i += (c))
#define FOR1_R(a) for (ll i = (a)-1; i >= ll(0); --i)
#define FOR2_R(i, a) for (ll i = (a)-1; i >= ll(0); --i)
#define FOR3_R(i, a, b) for (ll i = (b)-1; i >= ll(a); --i)
#define overload4(a, b, c, d, e, ...) e
#define overload3(a, b, c, d, ...) d
#define FOR(...) overload4(__VA_ARGS__, FOR4, FOR3, FOR2, FOR1)(__VA_ARGS__)
#define FOR_R(...) overload3(__VA_ARGS__, FOR3_R, FOR2_R, FOR1_R)(__VA_ARGS__)

#define FOR_subset(t, s) \
  for (ll t = (s); t >= 0; t = (t == 0 ? -1 : (t - 1) & (s)))
#define all(x) x.begin(), x.end()
#define len(x) ll(x.size())
#define elif else if

#define eb emplace_back
#define mp make_pair
#define mt make_tuple
#define fi first
#define se second

#define stoi stoll

int popcnt(int x) { return __builtin_popcount(x); }
int popcnt(u32 x) { return __builtin_popcount(x); }
int popcnt(ll x) { return __builtin_popcountll(x); }
int popcnt(u64 x) { return __builtin_popcountll(x); }
// (0, 1, 2, 3, 4) -> (-1, 0, 1, 1, 2)
int topbit(int x) { return (x == 0 ? -1 : 31 - __builtin_clz(x)); }
int topbit(u32 x) { return (x == 0 ? -1 : 31 - __builtin_clz(x)); }
int topbit(ll x) { return (x == 0 ? -1 : 63 - __builtin_clzll(x)); }
int topbit(u64 x) { return (x == 0 ? -1 : 63 - __builtin_clzll(x)); }
// (0, 1, 2, 3, 4) -> (-1, 0, 1, 0, 2)
int lowbit(int x) { return (x == 0 ? -1 : __builtin_ctz(x)); }
int lowbit(u32 x) { return (x == 0 ? -1 : __builtin_ctz(x)); }
int lowbit(ll x) { return (x == 0 ? -1 : __builtin_ctzll(x)); }
int lowbit(u64 x) { return (x == 0 ? -1 : __builtin_ctzll(x)); }

template <typename T, typename U>
T ceil(T x, U y) {
  return (x > 0 ? (x + y - 1) / y : x / y);
}
template <typename T, typename U>
T floor(T x, U y) {
  return (x > 0 ? x / y : (x - y + 1) / y);
}
template <typename T, typename U>
pair<T, T> divmod(T x, U y) {
  T q = floor(x, y);
  return {q, x - q * y};
}

template <typename T, typename U>
T SUM(const vector<U> &A) {
  T sum = 0;
  for (auto &&a: A) sum += a;
  return sum;
}

#define MIN(v) *min_element(all(v))
#define MAX(v) *max_element(all(v))
#define LB(c, x) distance((c).begin(), lower_bound(all(c), (x)))
#define UB(c, x) distance((c).begin(), upper_bound(all(c), (x)))
#define UNIQUE(x) \
  sort(all(x)), x.erase(unique(all(x)), x.end()), x.shrink_to_fit()

template <typename T>
T POP(deque<T> &que) {
  T a = que.front();
  que.pop_front();
  return a;
}
template <typename T>
T POP(pq<T> &que) {
  T a = que.top();
  que.pop();
  return a;
}
template <typename T>
T POP(pqg<T> &que) {
  assert(!que.empty());
  T a = que.top();
  que.pop();
  return a;
}
template <typename T>
T POP(vc<T> &que) {
  assert(!que.empty());
  T a = que.back();
  que.pop_back();
  return a;
}

template <typename F>
ll binary_search(F check, ll ok, ll ng, bool check_ok = true) {
  if (check_ok) assert(check(ok));
  while (abs(ok - ng) > 1) {
    auto x = (ng + ok) / 2;
    tie(ok, ng) = (check(x) ? mp(x, ng) : mp(ok, x));
  }
  return ok;
}
template <typename F>
double binary_search_real(F check, double ok, double ng, int iter = 100) {
  FOR(iter) {
    double x = (ok + ng) / 2;
    tie(ok, ng) = (check(x) ? mp(x, ng) : mp(ok, x));
  }
  return (ok + ng) / 2;
}

template <class T, class S>
inline bool chmax(T &a, const S &b) {
  return (a < b ? a = b, 1 : 0);
}
template <class T, class S>
inline bool chmin(T &a, const S &b) {
  return (a > b ? a = b, 1 : 0);
}

// ? は -1
vc<int> s_to_vi(const string &S, char first_char) {
  vc<int> A(S.size());
  FOR(i, S.size()) { A[i] = (S[i] != '?' ? S[i] - first_char : -1); }
  return A;
}

template <typename T, typename U>
vector<T> cumsum(vector<U> &A, int off = 1) {
  int N = A.size();
  vector<T> B(N + 1);
  FOR(i, N) { B[i + 1] = B[i] + A[i]; }
  if (off == 0) B.erase(B.begin());
  return B;
}

// stable sort
template <typename T>
vector<int> argsort(const vector<T> &A) {
  vector<int> ids(len(A));
  iota(all(ids), 0);
  sort(all(ids),
       [&](int i, int j) { return (A[i] == A[j] ? i < j : A[i] < A[j]); });
  return ids;
}

// A[I[0]], A[I[1]], ...
template <typename T>
vc<T> rearrange(const vc<T> &A, const vc<int> &I) {
  vc<T> B(len(I));
  FOR(i, len(I)) B[i] = A[I[i]];
  return B;
}
#endif
#line 1 "library/other/io.hpp"
// based on yosupo's fastio
#include <unistd.h>

namespace fastio {
#define FASTIO
// クラスが read(), print() を持っているかを判定するメタ関数
struct has_write_impl {
  template <class T>
  static auto check(T &&x) -> decltype(x.write(), std::true_type{});

  template <class T>
  static auto check(...) -> std::false_type;
};

template <class T>
class has_write : public decltype(has_write_impl::check<T>(std::declval<T>())) {
};

struct has_read_impl {
  template <class T>
  static auto check(T &&x) -> decltype(x.read(), std::true_type{});

  template <class T>
  static auto check(...) -> std::false_type;
};

template <class T>
class has_read : public decltype(has_read_impl::check<T>(std::declval<T>())) {};

struct Scanner {
  FILE *fp;
  char line[(1 << 15) + 1];
  size_t st = 0, ed = 0;
  void reread() {
    memmove(line, line + st, ed - st);
    ed -= st;
    st = 0;
    ed += fread(line + ed, 1, (1 << 15) - ed, fp);
    line[ed] = '\0';
  }
  bool succ() {
    while (true) {
      if (st == ed) {
        reread();
        if (st == ed) return false;
      }
      while (st != ed && isspace(line[st])) st++;
      if (st != ed) break;
    }
    if (ed - st <= 50) {
      bool sep = false;
      for (size_t i = st; i < ed; i++) {
        if (isspace(line[i])) {
          sep = true;
          break;
        }
      }
      if (!sep) reread();
    }
    return true;
  }
  template <class T, enable_if_t<is_same<T, string>::value, int> = 0>
  bool read_single(T &ref) {
    if (!succ()) return false;
    while (true) {
      size_t sz = 0;
      while (st + sz < ed && !isspace(line[st + sz])) sz++;
      ref.append(line + st, sz);
      st += sz;
      if (!sz || st != ed) break;
      reread();
    }
    return true;
  }
  template <class T, enable_if_t<is_integral<T>::value, int> = 0>
  bool read_single(T &ref) {
    if (!succ()) return false;
    bool neg = false;
    if (line[st] == '-') {
      neg = true;
      st++;
    }
    ref = T(0);
    while (isdigit(line[st])) { ref = 10 * ref + (line[st++] & 0xf); }
    if (neg) ref = -ref;
    return true;
  }
  template <typename T,
            typename enable_if<has_read<T>::value>::type * = nullptr>
  inline bool read_single(T &x) {
    x.read();
    return true;
  }
  bool read_single(double &ref) {
    string s;
    if (!read_single(s)) return false;
    ref = std::stod(s);
    return true;
  }
  bool read_single(char &ref) {
    string s;
    if (!read_single(s) || s.size() != 1) return false;
    ref = s[0];
    return true;
  }
  template <class T>
  bool read_single(vector<T> &ref) {
    for (auto &d: ref) {
      if (!read_single(d)) return false;
    }
    return true;
  }
  template <class T, class U>
  bool read_single(pair<T, U> &p) {
    return (read_single(p.first) && read_single(p.second));
  }
  template <size_t N = 0, typename T>
  void read_single_tuple(T &t) {
    if constexpr (N < std::tuple_size<T>::value) {
      auto &x = std::get<N>(t);
      read_single(x);
      read_single_tuple<N + 1>(t);
    }
  }
  template <class... T>
  bool read_single(tuple<T...> &tpl) {
    read_single_tuple(tpl);
    return true;
  }
  void read() {}
  template <class H, class... T>
  void read(H &h, T &... t) {
    bool f = read_single(h);
    assert(f);
    read(t...);
  }
  Scanner(FILE *fp) : fp(fp) {}
};

struct Printer {
  Printer(FILE *_fp) : fp(_fp) {}
  ~Printer() { flush(); }

  static constexpr size_t SIZE = 1 << 15;
  FILE *fp;
  char line[SIZE], small[50];
  size_t pos = 0;
  void flush() {
    fwrite(line, 1, pos, fp);
    pos = 0;
  }
  void write(const char val) {
    if (pos == SIZE) flush();
    line[pos++] = val;
  }
  template <class T, enable_if_t<is_integral<T>::value, int> = 0>
  void write(T val) {
    if (pos > (1 << 15) - 50) flush();
    if (val == 0) {
      write('0');
      return;
    }
    if (val < 0) {
      write('-');
      val = -val; // todo min
    }
    size_t len = 0;
    while (val) {
      small[len++] = char(0x30 | (val % 10));
      val /= 10;
    }
    for (size_t i = 0; i < len; i++) { line[pos + i] = small[len - 1 - i]; }
    pos += len;
  }
  void write(const string s) {
    for (char c: s) write(c);
  }
  void write(const char *s) {
    size_t len = strlen(s);
    for (size_t i = 0; i < len; i++) write(s[i]);
  }
  void write(const double x) {
    ostringstream oss;
    oss << fixed << setprecision(15) << x;
    string s = oss.str();
    write(s);
  }
  void write(const long double x) {
    ostringstream oss;
    oss << fixed << setprecision(15) << x;
    string s = oss.str();
    write(s);
  }
  template <typename T,
            typename enable_if<has_write<T>::value>::type * = nullptr>
  inline void write(T x) {
    x.write();
  }
  template <class T>
  void write(const vector<T> val) {
    auto n = val.size();
    for (size_t i = 0; i < n; i++) {
      if (i) write(' ');
      write(val[i]);
    }
  }
  template <class T, class U>
  void write(const pair<T, U> val) {
    write(val.first);
    write(' ');
    write(val.second);
  }
  template <size_t N = 0, typename T>
  void write_tuple(const T t) {
    if constexpr (N < std::tuple_size<T>::value) {
      if constexpr (N > 0) { write(' '); }
      const auto x = std::get<N>(t);
      write(x);
      write_tuple<N + 1>(t);
    }
  }
  template <class... T>
  bool write(tuple<T...> tpl) {
    write_tuple(tpl);
    return true;
  }
  template <class T, size_t S>
  void write(const array<T, S> val) {
    auto n = val.size();
    for (size_t i = 0; i < n; i++) {
      if (i) write(' ');
      write(val[i]);
    }
  }
  void write(i128 val) {
    string s;
    bool negative = 0;
    if (val < 0) {
      negative = 1;
      val = -val;
    }
    while (val) {
      s += '0' + int(val % 10);
      val /= 10;
    }
    if (negative) s += "-";
    reverse(all(s));
    if (len(s) == 0) s = "0";
    write(s);
  }
};
Scanner scanner = Scanner(stdin);
Printer printer = Printer(stdout);
void flush() { printer.flush(); }
void print() { printer.write('\n'); }
template <class Head, class... Tail>
void print(Head &&head, Tail &&... tail) {
  printer.write(head);
  if (sizeof...(Tail)) printer.write(' ');
  print(forward<Tail>(tail)...);
}

void read() {}
template <class Head, class... Tail>
void read(Head &head, Tail &... tail) {
  scanner.read(head);
  read(tail...);
}
} // namespace fastio
using fastio::print;
using fastio::flush;
using fastio::read;

#define INT(...)   \
  int __VA_ARGS__; \
  read(__VA_ARGS__)
#define LL(...)   \
  ll __VA_ARGS__; \
  read(__VA_ARGS__)
#define STR(...)      \
  string __VA_ARGS__; \
  read(__VA_ARGS__)
#define CHAR(...)   \
  char __VA_ARGS__; \
  read(__VA_ARGS__)
#define DBL(...)      \
  double __VA_ARGS__; \
  read(__VA_ARGS__)

#define VEC(type, name, size) \
  vector<type> name(size);    \
  read(name)
#define VV(type, name, h, w)                     \
  vector<vector<type>> name(h, vector<type>(w)); \
  read(name)

void YES(bool t = 1) { print(t ? "YES" : "NO"); }
void NO(bool t = 1) { YES(!t); }
void Yes(bool t = 1) { print(t ? "Yes" : "No"); }
void No(bool t = 1) { Yes(!t); }
void yes(bool t = 1) { print(t ? "yes" : "no"); }
void no(bool t = 1) { yes(!t); }
#line 3 "main.cpp"

#line 2 "library/ds/unionfind/unionfind.hpp"

struct UnionFind {
  int n, n_comp;
  vc<int> dat; // par or (-size)
  UnionFind(int n = 0) { build(n); }

  void build(int m) {
    n = m, n_comp = m;
    dat.assign(n, -1);
  }

  void reset() { build(n); }

  int operator[](int x) {
    while (dat[x] >= 0) {
      int pp = dat[dat[x]];
      if (pp < 0) { return dat[x]; }
      x = dat[x] = pp;
    }
    return x;
  }

  ll size(int x) {
    x = (*this)[x];
    return -dat[x];
  }

  bool merge(int x, int y) {
    x = (*this)[x], y = (*this)[y];
    if (x == y) return false;
    if (-dat[x] < -dat[y]) swap(x, y);
    dat[x] += dat[y], dat[y] = x, n_comp--;
    return true;
  }
};
#line 2 "library/graph/base.hpp"

template <typename T>
struct Edge {
  int frm, to;
  T cost;
  int id;
};

template <typename T = int, bool directed = false>
struct Graph {
  int N, M;
  using cost_type = T;
  using edge_type = Edge<T>;
  vector<edge_type> edges;
  vector<int> indptr;
  vector<edge_type> csr_edges;
  vc<int> vc_deg, vc_indeg, vc_outdeg;
  bool prepared;

  class OutgoingEdges {
  public:
    OutgoingEdges(const Graph* G, int l, int r) : G(G), l(l), r(r) {}

    const edge_type* begin() const {
      if (l == r) { return 0; }
      return &G->csr_edges[l];
    }

    const edge_type* end() const {
      if (l == r) { return 0; }
      return &G->csr_edges[r];
    }

  private:
    const Graph* G;
    int l, r;
  };

  bool is_prepared() { return prepared; }
  constexpr bool is_directed() { return directed; }

  Graph() : N(0), M(0), prepared(0) {}
  Graph(int N) : N(N), M(0), prepared(0) {}

  void build(int n) {
    N = n, M = 0;
    prepared = 0;
    edges.clear();
    indptr.clear();
    csr_edges.clear();
    vc_deg.clear();
    vc_indeg.clear();
    vc_outdeg.clear();
  }

  void add(int frm, int to, T cost = 1, int i = -1) {
    assert(!prepared);
    assert(0 <= frm && 0 <= to && to < N);
    if (i == -1) i = M;
    auto e = edge_type({frm, to, cost, i});
    edges.eb(e);
    ++M;
  }

  // wt, off
  void read_tree(bool wt = false, int off = 1) { read_graph(N - 1, wt, off); }

  void read_graph(int M, bool wt = false, int off = 1) {
    for (int m = 0; m < M; ++m) {
      INT(a, b);
      a -= off, b -= off;
      if (!wt) {
        add(a, b);
      } else {
        T c;
        read(c);
        add(a, b, c);
      }
    }
    build();
  }

  void build() {
    assert(!prepared);
    prepared = true;
    indptr.assign(N + 1, 0);
    for (auto&& e: edges) {
      indptr[e.frm + 1]++;
      if (!directed) indptr[e.to + 1]++;
    }
    for (int v = 0; v < N; ++v) { indptr[v + 1] += indptr[v]; }
    auto counter = indptr;
    csr_edges.resize(indptr.back() + 1);
    for (auto&& e: edges) {
      csr_edges[counter[e.frm]++] = e;
      if (!directed)
        csr_edges[counter[e.to]++] = edge_type({e.to, e.frm, e.cost, e.id});
    }
  }

  OutgoingEdges operator[](int v) const {
    assert(prepared);
    return {this, indptr[v], indptr[v + 1]};
  }

  vc<int> deg_array() {
    if (vc_deg.empty()) calc_deg();
    return vc_deg;
  }

  pair<vc<int>, vc<int>> deg_array_inout() {
    if (vc_indeg.empty()) calc_deg_inout();
    return {vc_indeg, vc_outdeg};
  }

  int deg(int v) {
    if (vc_deg.empty()) calc_deg();
    return vc_deg[v];
  }

  int in_deg(int v) {
    if (vc_indeg.empty()) calc_deg_inout();
    return vc_indeg[v];
  }

  int out_deg(int v) {
    if (vc_outdeg.empty()) calc_deg_inout();
    return vc_outdeg[v];
  }

  void debug() {
    print("Graph");
    if (!prepared) {
      print("frm to cost id");
      for (auto&& e: edges) print(e.frm, e.to, e.cost, e.id);
    } else {
      print("indptr", indptr);
      print("frm to cost id");
      FOR(v, N) for (auto&& e: (*this)[v]) print(e.frm, e.to, e.cost, e.id);
    }
  }

  vc<int> new_idx;
  vc<bool> used_e;

  // G における頂点 V[i] が、新しいグラフで i になるようにする
  // {G, es}
  pair<Graph<T, directed>, vc<int>> rearrange(vc<int> V) {
    if (len(new_idx) != N) new_idx.assign(N, -1);
    if (len(used_e) != M) used_e.assign(M, 0);
    int n = len(V);
    FOR(i, n) new_idx[V[i]] = i;
    Graph<T, directed> G(n);
    vc<int> es;
    FOR(i, n) {
      for (auto&& e: (*this)[V[i]]) {
        if (used_e[e.id]) continue;
        int a = e.frm, b = e.to;
        if (new_idx[a] != -1 && new_idx[b] != -1) {
          used_e[e.id] = 1;
          G.add(new_idx[a], new_idx[b], e.cost);
          es.eb(e.id);
        }
      }
    }
    FOR(i, n) new_idx[V[i]] = -1;
    for (auto&& eid: es) used_e[eid] = 0;
    G.build();
    return {G, es};
  }

private:
  void calc_deg() {
    assert(vc_deg.empty());
    vc_deg.resize(N);
    for (auto&& e: edges) vc_deg[e.frm]++, vc_deg[e.to]++;
  }

  void calc_deg_inout() {
    assert(vc_indeg.empty());
    vc_indeg.resize(N);
    vc_outdeg.resize(N);
    for (auto&& e: edges) { vc_indeg[e.to]++, vc_outdeg[e.frm]++; }
  }
};
#line 2 "library/graph/tree.hpp"

#line 4 "library/graph/tree.hpp"

// HLD euler tour をとっていろいろ。
// 木以外、非連結でも dfs 順序や親がとれる。
template <typename GT>
struct Tree {
  using Graph_type = GT;
  GT &G;
  using WT = typename GT::cost_type;
  int N;
  vector<int> LID, RID, head, V, parent, VtoE;
  vc<int> depth;
  vc<WT> depth_weighted;

  Tree(GT &G, int r = 0, bool hld = 1) : G(G) { build(r, hld); }

  void build(int r = 0, bool hld = 1) {
    if (r == -1) return; // build を遅延したいとき
    N = G.N;
    LID.assign(N, -1), RID.assign(N, -1), head.assign(N, r);
    V.assign(N, -1), parent.assign(N, -1), VtoE.assign(N, -1);
    depth.assign(N, -1), depth_weighted.assign(N, 0);
    assert(G.is_prepared());
    int t1 = 0;
    dfs_sz(r, -1, hld);
    dfs_hld(r, t1);
  }

  void dfs_sz(int v, int p, bool hld) {
    auto &sz = RID;
    parent[v] = p;
    depth[v] = (p == -1 ? 0 : depth[p] + 1);
    sz[v] = 1;
    int l = G.indptr[v], r = G.indptr[v + 1];
    auto &csr = G.csr_edges;
    // 使う辺があれば先頭にする
    for (int i = r - 2; i >= l; --i) {
      if (hld && depth[csr[i + 1].to] == -1) swap(csr[i], csr[i + 1]);
    }
    int hld_sz = 0;
    for (int i = l; i < r; ++i) {
      auto e = csr[i];
      if (depth[e.to] != -1) continue;
      depth_weighted[e.to] = depth_weighted[v] + e.cost;
      VtoE[e.to] = e.id;
      dfs_sz(e.to, v, hld);
      sz[v] += sz[e.to];
      if (hld && chmax(hld_sz, sz[e.to]) && l < i) { swap(csr[l], csr[i]); }
    }
  }

  void dfs_hld(int v, int &times) {
    LID[v] = times++;
    RID[v] += LID[v];
    V[LID[v]] = v;
    bool heavy = true;
    for (auto &&e: G[v]) {
      if (depth[e.to] <= depth[v]) continue;
      head[e.to] = (heavy ? head[v] : e.to);
      heavy = false;
      dfs_hld(e.to, times);
    }
  }

  vc<int> heavy_path_at(int v) {
    vc<int> P = {v};
    while (1) {
      int a = P.back();
      for (auto &&e: G[a]) {
        if (e.to != parent[a] && head[e.to] == v) {
          P.eb(e.to);
          break;
        }
      }
      if (P.back() == a) break;
    }
    return P;
  }

  int e_to_v(int eid) {
    auto e = G.edges[eid];
    return (parent[e.frm] == e.to ? e.frm : e.to);
  }
  int v_to_e(int v) { return VtoE[v]; }

  int ELID(int v) { return 2 * LID[v] - depth[v]; }
  int ERID(int v) { return 2 * RID[v] - depth[v] - 1; }

  /* k: 0-indexed */
  int LA(int v, int k) {
    assert(k <= depth[v]);
    while (1) {
      int u = head[v];
      if (LID[v] - k >= LID[u]) return V[LID[v] - k];
      k -= LID[v] - LID[u] + 1;
      v = parent[u];
    }
  }
  int la(int u, int v) { return LA(u, v); }

  int LCA(int u, int v) {
    for (;; v = parent[head[v]]) {
      if (LID[u] > LID[v]) swap(u, v);
      if (head[u] == head[v]) return u;
    }
  }
  // root を根とした場合の lca
  int LCA_root(int u, int v, int root) {
    return LCA(u, v) ^ LCA(u, root) ^ LCA(v, root);
  }
  int lca(int u, int v) { return LCA(u, v); }
  int lca_root(int u, int v, int root) { return LCA_root(u, v, root); }

  int subtree_size(int v, int root = -1) {
    if (root == -1) return RID[v] - LID[v];
    if (v == root) return N;
    int x = jump(v, root, 1);
    if (in_subtree(v, x)) return RID[v] - LID[v];
    return N - RID[x] + LID[x];
  }

  int dist(int a, int b) {
    int c = LCA(a, b);
    return depth[a] + depth[b] - 2 * depth[c];
  }

  WT dist_weighted(int a, int b) {
    int c = LCA(a, b);
    return depth_weighted[a] + depth_weighted[b] - WT(2) * depth_weighted[c];
  }

  // a is in b
  bool in_subtree(int a, int b) { return LID[b] <= LID[a] && LID[a] < RID[b]; }

  int jump(int a, int b, ll k) {
    if (k == 1) {
      if (a == b) return -1;
      return (in_subtree(b, a) ? LA(b, depth[b] - depth[a] - 1) : parent[a]);
    }
    int c = LCA(a, b);
    int d_ac = depth[a] - depth[c];
    int d_bc = depth[b] - depth[c];
    if (k > d_ac + d_bc) return -1;
    if (k <= d_ac) return LA(a, k);
    return LA(b, d_ac + d_bc - k);
  }

  vc<int> collect_child(int v) {
    vc<int> res;
    for (auto &&e: G[v])
      if (e.to != parent[v]) res.eb(e.to);
    return res;
  }

  vc<pair<int, int>> get_path_decomposition(int u, int v, bool edge) {
    // [始点, 終点] の"閉"区間列。
    vc<pair<int, int>> up, down;
    while (1) {
      if (head[u] == head[v]) break;
      if (LID[u] < LID[v]) {
        down.eb(LID[head[v]], LID[v]);
        v = parent[head[v]];
      } else {
        up.eb(LID[u], LID[head[u]]);
        u = parent[head[u]];
      }
    }
    if (LID[u] < LID[v]) down.eb(LID[u] + edge, LID[v]);
    elif (LID[v] + edge <= LID[u]) up.eb(LID[u], LID[v] + edge);
    reverse(all(down));
    up.insert(up.end(), all(down));
    return up;
  }

  vc<int> restore_path(int u, int v) {
    vc<int> P;
    for (auto &&[a, b]: get_path_decomposition(u, v, 0)) {
      if (a <= b) {
        FOR(i, a, b + 1) P.eb(V[i]);
      } else {
        FOR_R(i, b, a + 1) P.eb(V[i]);
      }
    }
    return P;
  }
};
#line 2 "library/alg/monoid/add.hpp"

template <typename X>
struct Monoid_Add {
  using value_type = X;
  static constexpr X op(const X &x, const X &y) noexcept { return x + y; }
  static constexpr X inverse(const X &x) noexcept { return -x; }
  static constexpr X power(const X &x, ll n) noexcept { return X(n) * x; }
  static constexpr X unit() { return X(0); }
  static constexpr bool commute = true;
};
#line 3 "library/ds/fenwicktree/fenwicktree.hpp"

template <typename Monoid>
struct FenwickTree {
  using G = Monoid;
  using E = typename G::value_type;
  int n;
  vector<E> dat;
  E total;

  FenwickTree() {}
  FenwickTree(int n) { build(n); }
  template <typename F>
  FenwickTree(int n, F f) {
    build(n, f);
  }
  FenwickTree(const vc<E>& v) { build(v); }

  void build(int m) {
    n = m;
    dat.assign(m, G::unit());
    total = G::unit();
  }
  void build(const vc<E>& v) {
    build(len(v), [&](int i) -> E { return v[i]; });
  }
  template <typename F>
  void build(int m, F f) {
    n = m;
    dat.clear();
    dat.reserve(n);
    total = G::unit();
    FOR(i, n) { dat.eb(f(i)); }
    for (int i = 1; i <= n; ++i) {
      int j = i + (i & -i);
      if (j <= n) dat[j - 1] = G::op(dat[i - 1], dat[j - 1]);
    }
    total = prefix_sum(m);
  }

  E prod_all() { return total; }
  E sum_all() { return total; }
  E sum(int k) { return prefix_sum(k); }
  E prod(int k) { return prefix_prod(k); }
  E prefix_sum(int k) { return prefix_prod(k); }
  E prefix_prod(int k) {
    chmin(k, n);
    E ret = G::unit();
    for (; k > 0; k -= k & -k) ret = G::op(ret, dat[k - 1]);
    return ret;
  }
  E sum(int L, int R) { return prod(L, R); }
  E prod(int L, int R) {
    chmax(L, 0), chmin(R, n);
    if (L == 0) return prefix_prod(R);
    assert(0 <= L && L <= R && R <= n);
    E pos = G::unit(), neg = G::unit();
    while (L < R) { pos = G::op(pos, dat[R - 1]), R -= R & -R; }
    while (R < L) { neg = G::op(neg, dat[L - 1]), L -= L & -L; }
    return G::op(pos, G::inverse(neg));
  }

  void add(int k, E x) { multiply(k, x); }
  void multiply(int k, E x) {
    static_assert(G::commute);
    total = G::op(total, x);
    for (++k; k <= n; k += k & -k) dat[k - 1] = G::op(dat[k - 1], x);
  }

  template <class F>
  int max_right(const F check) {
    assert(check(G::unit()));
    int i = 0;
    E s = G::unit();
    int k = 1;
    while (2 * k <= n) k *= 2;
    while (k) {
      if (i + k - 1 < len(dat)) {
        E t = G::op(s, dat[i + k - 1]);
        if (check(t)) { i += k, s = t; }
      }
      k >>= 1;
    }
    return i;
  }

  int kth(E k) {
    return max_right([&k](E x) -> bool { return x <= k; });
  }
};
#line 3 "library/graph/ds/tree_abelgroup.hpp"

template <typename TREE, typename AbelGroup, bool edge, bool path_query,
          bool subtree_query>
struct Tree_AbelGroup {
  using X = typename AbelGroup::value_type;
  TREE &tree;
  int N;
  FenwickTree<AbelGroup> bit, bit_subtree;

  Tree_AbelGroup(TREE &tree) : tree(tree), N(tree.N) {
    build([](int i) -> X { return AbelGroup::unit(); });
  }

  Tree_AbelGroup(TREE &tree, vc<X> &dat) : tree(tree), N(tree.N) {
    build([&](int i) -> X { return dat[i]; });
  }

  template <typename F>
  Tree_AbelGroup(TREE &tree, F f) : tree(tree), N(tree.N) {
    build(f);
  }

  template <typename F>
  void build(F f) {
    vc<X> bit_raw_1(2 * N);
    vc<X> bit_raw_2(N);
    if (!edge) {
      FOR(v, N) {
        X x = f(v);
        bit_raw_1[tree.ELID(v)] = x;
        bit_raw_1[tree.ERID(v)] = AbelGroup::inverse(x);
        bit_raw_2[tree.LID[v]] = x;
      }
    } else {
      FOR(e, N - 1) {
        int v = tree.e_to_v(e);
        X x = f(v);
        bit_raw_1[tree.ELID(v)] = x;
        bit_raw_1[tree.ERID(v)] = AbelGroup::inverse(x);
        bit_raw_2[tree.LID[v]] = x;
      }
    }
    bit.build(bit_raw_1);
    bit_subtree.build(bit_raw_2);
  }

  void add(int i, X x) {
    int v = (edge ? tree.e_to_v(i) : i);
    if (path_query) {
      X inv_x = AbelGroup::inverse(x);
      bit.add(tree.ELID(v), x);
      bit.add(tree.ERID(v), inv_x);
    }
    if (subtree_query) bit_subtree.add(tree.LID[v], x);
  }

  X prod_path(int frm, int to) {
    assert(path_query);
    int lca = tree.LCA(frm, to);
    // [frm, lca)
    X x1 = bit.prod(tree.ELID(lca) + 1, tree.ELID(frm) + 1);
    // edge なら (lca, to]、vertex なら [lca, to]
    X x2 = bit.prod(tree.ELID(lca) + edge, tree.ELID(to) + 1);
    return AbelGroup::op(x1, x2);
  }

  X prod_subtree(int u) {
    assert(subtree_query);
    int l = tree.LID[u], r = tree.RID[u];
    return bit_subtree.prod(l + edge, r);
  }
};
#line 8 "main.cpp"

void solve() {
  LL(N, M);
  ll B = 0;
  while (B * B < N) ++B;
  Graph<int, 0> G(N);
  UnionFind uf(N);
  FOR(M) {
    INT(a, b);
    --a, --b;
    if (uf.merge(a, b)) G.add(a, b);
  }
  G.build();
  Tree<decltype(G)> tree(G);

  Tree_AbelGroup<decltype(tree), Monoid_Add<int>, 0, 1, 0> TA(tree);

  auto dep = tree.depth;
  pq<pi> que;
  FOR(v, N) que.emplace(dep[v], v);

  vi ANS;
  while (len(que)) {
    auto [dv, v] = POP(que);
    if (TA.prod_path(0, v)) continue;
    FOR(B) {
      if (v == 0) break;
      v = tree.parent[v];
    }
    ANS.eb(v);
    TA.add(v, 1);
  }
  for (auto&& x: ANS) ++x;
  print(len(ANS));
  print(ANS);
}

signed main() {
  INT(T);
  FOR(T) solve();
  return 0;
}

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 1ms
memory: 3524kb

input:

2
4 3
1 2
2 3
3 4
6 7
1 2
2 3
3 1
1 4
4 5
5 6
6 4

output:

2
2 1
1
1

result:

ok correct (2 test cases)

Test #2:

score: 0
Accepted
time: 22ms
memory: 3544kb

input:

10000
15 14
13 12
5 4
9 8
11 12
15 14
10 9
14 13
2 3
2 1
6 5
10 11
3 4
7 6
8 7
6 5
2 1
2 4
4 6
2 3
3 5
10 9
8 3
9 4
5 6
5 10
3 2
5 4
2 7
1 2
4 3
2 1
2 1
2 1
2 1
9 8
9 8
5 4
1 2
6 5
3 4
3 2
7 8
7 6
2 1
1 2
14 13
3 10
5 6
2 9
11 4
2 3
2 1
8 7
13 6
5 4
5 12
6 7
4 3
7 14
16 15
2 3
2 1
6 10
6 9
6 4
9 11
...

output:

3
11 6 1
1
1
2
2 1
1
1
1
1
3
6 2 1
1
1
2
4 1
3
10 3 1
1
1
4
15 9 3 1
2
3 1
2
2 1
2
5 1
1
1
3
11 6 1
1
1
1
1
2
2 1
1
1
2
2 1
2
3 1
2
4 1
2
5 1
1
1
3
11 6 1
1
1
2
5 1
1
1
1
1
4
16 10 4 1
2
2 1
2
4 1
3
7 4 1
1
1
2
3 1
2
2 1
2
3 1
3
7 6 1
1
1
3
8 3 1
1
1
2
3 1
2
2 1
1
1
2
6 1
2
3 1
2
3 1
2
5 1
1
1
3
13 ...

result:

ok correct (10000 test cases)

Test #3:

score: 0
Accepted
time: 34ms
memory: 3972kb

input:

100
2000 1999
529 528
885 884
1221 1222
375 374
245 244
758 757
711 710
1521 1522
1875 1874
749 750
823 822
1959 1958
1767 1766
155 154
631 632
825 824
1330 1331
457 456
1344 1343
1817 1818
413 414
582 583
1828 1827
1335 1336
654 655
162 161
1668 1667
1966 1967
1472 1471
1185 1184
518 517
1509 1510
...

output:

44
1955 1909 1863 1817 1771 1725 1679 1633 1587 1541 1495 1449 1403 1357 1311 1265 1219 1173 1127 1081 1035 989 943 897 851 805 759 713 667 621 575 529 483 437 391 345 299 253 207 161 115 69 23 1
1
1
23
956 911 866 821 776 731 686 641 596 551 506 461 416 371 326 281 236 191 146 101 56 11 1
6
1170 10...

result:

ok correct (100 test cases)

Test #4:

score: 0
Accepted
time: 31ms
memory: 8164kb

input:

10
14914 14913
13959 13958
3643 3642
4582 4581
13378 13379
981 980
12901 12902
12355 12356
14692 14691
9670 9669
14632 14631
1441 1440
1367 1368
6237 6238
8297 8298
1021 1020
5096 5097
4773 4774
7778 7779
3013 3014
5536 5535
11621 11620
13904 13903
3050 3049
14179 14178
7471 7472
13380 13381
7403 74...

output:

121
14791 14667 14543 14419 14295 14171 14047 13923 13799 13675 13551 13427 13303 13179 13055 12931 12807 12683 12559 12435 12311 12187 12063 11939 11815 11691 11567 11443 11319 11195 11071 10947 10823 10699 10575 10451 10327 10203 10079 9955 9831 9707 9583 9459 9335 9211 9087 8963 8839 8715 8591 84...

result:

ok correct (10 test cases)

Test #5:

score: 0
Accepted
time: 47ms
memory: 6216kb

input:

10
20000 19999
6831 6760
15763 15900
10362 10184
5821 5880
17555 17389
16708 16574
11592 11436
186 209
19380 19313
8867 8718
12100 12237
16245 16110
18464 18568
4713 4665
17412 17578
18666 18750
4360 4322
12350 12502
4054 4103
2874 2849
8097 8202
14489 14639
1056 1016
13500 13581
2435 2391
199 173
8...

output:

4
6126 3269 1143 1
5
10809 8283 178 176 1
5
11257 8040 3276 471 1
5
10584 9863 3873 3415 1
6
15169 14623 8672 8665 1487 1
6
15046 6159 4075 2577 207 1
7
15985 8593 6581 1059 972 256 1
6
7843 6192 5415 2418 266 1
6
14312 1588 1088 1025 27 1
5
8901 8799 7775 2515 1

result:

ok correct (10 test cases)

Test #6:

score: 0
Accepted
time: 46ms
memory: 48468kb

input:

1
200000 199999
136649 136648
44943 44944
7148 7149
50332 50333
149967 149966
28976 28975
78549 78550
178698 178697
96434 96433
7859 7858
88976 88977
23348 23347
161682 161681
125393 125392
67892 67893
73592 73593
179054 179055
110841 110842
163714 163715
7982 7981
56309 56310
196486 196485
19176 19...

output:

446
199552 199103 198654 198205 197756 197307 196858 196409 195960 195511 195062 194613 194164 193715 193266 192817 192368 191919 191470 191021 190572 190123 189674 189225 188776 188327 187878 187429 186980 186531 186082 185633 185184 184735 184286 183837 183388 182939 182490 182041 181592 181143 18...

result:

ok correct (1 test case)

Test #7:

score: 0
Accepted
time: 34ms
memory: 39808kb

input:

1
200000 199999
58280 58281
132016 32016
45157 45158
35446 35445
158979 58979
185831 85831
74289 174289
195645 95645
31857 131857
168766 68766
95607 95606
39817 39818
58215 158215
74893 74894
18897 118897
63013 163013
58501 58502
94475 194475
77574 77573
152977 52977
3731 103731
20407 20408
186570 8...

output:

224
99553 99105 98657 98209 97761 97313 96865 96417 95969 95521 95073 94625 94177 93729 93281 92833 92385 91937 91489 91041 90593 90145 89697 89249 88801 88353 87905 87457 87009 86561 86113 85665 85217 84769 84321 83873 83425 82977 82529 82081 81633 81185 80737 80289 79841 79393 78945 78497 78049 77...

result:

ok correct (1 test case)

Test #8:

score: 0
Accepted
time: 54ms
memory: 32780kb

input:

1
200000 199999
84088 84001
74829 74679
40726 41179
113019 113238
112813 113025
77336 77177
60908 61208
4521 4639
144249 144094
102763 102692
112856 113070
2428 2356
114005 113754
168454 168270
114538 114311
36802 36341
170182 170306
31641 32012
92503 92395
143570 143702
6871 6715
51503 51997
140883...

output:

6
149019 118805 107919 81894 4044 1

result:

ok correct (1 test case)

Test #9:

score: 0
Accepted
time: 12ms
memory: 3736kb

input:

1000
11 19
8 11
4 11
2 11
2 3
8 3
6 1
6 4
11 5
5 3
10 8
7 10
4 7
3 9
5 1
5 7
3 6
10 1
11 7
2 9
70 109
32 69
26 15
65 46
70 62
50 23
17 16
15 31
2 23
18 11
48 57
19 29
52 42
26 31
7 1
53 66
5 69
58 20
59 38
3 4
9 53
7 56
52 66
66 28
22 51
2 6
22 35
5 28
25 51
27 13
26 56
10 50
53 56
60 48
67 33
61 23...

output:

2
4 1
3
66 56 1
2
11 1
2
53 1
3
27 52 1
2
10 1
2
10 1
3
41 16 1
3
40 38 1
3
31 40 1
2
15 1
4
88 56 25 1
1
1
3
2 28 1
3
20 28 1
2
11 1
2
12 1
1
1
4
9 32 43 1
3
31 44 1
3
7 22 1
3
34 11 1
2
23 1
3
79 17 1
2
31 1
3
10 12 1
3
26 24 1
3
6 40 1
3
30 19 1
4
2 54 61 1
3
23 22 1
4
4 8 23 1
3
42 49 1
3
24 39 ...

result:

ok correct (1000 test cases)

Test #10:

score: 0
Accepted
time: 3ms
memory: 3568kb

input:

100
76 104
30 11
26 40
4 59
35 21
13 44
3 73
25 39
33 35
63 9
9 19
42 47
22 32
44 35
74 68
53 12
50 41
53 52
69 40
31 49
21 14
23 21
11 48
53 67
48 74
15 24
73 47
6 62
17 33
67 48
7 22
68 46
41 39
20 1
9 71
15 67
65 56
38 68
30 9
54 26
8 47
62 56
14 61
59 20
46 64
75 46
50 49
26 25
10 70
36 27
14 29...

output:

4
44 48 57 1
3
4 79 1
3
54 42 1
3
17 34 1
3
32 44 1
3
54 40 1
3
27 50 1
2
49 1
3
58 79 1
2
15 1
2
80 1
4
31 82 36 1
3
32 42 1
2
59 1
4
41 26 13 1
3
32 86 1
3
28 27 1
3
48 49 1
2
78 1
4
59 18 40 1
3
64 6 1
3
55 21 1
3
50 48 1
3
20 15 1
3
2 50 1
3
11 54 1
3
15 11 1
4
52 81 55 1
2
39 1
2
31 1
3
3 42 1
...

result:

ok correct (100 test cases)

Test #11:

score: 0
Accepted
time: 66ms
memory: 17132kb

input:

1
100000 1000000
70376 68374
69858 95507
48028 59467
27775 34161
858 86059
31468 25048
21313 82671
10952 18093
89665 50624
52742 11128
33566 41507
25913 22268
72131 67543
31387 42274
37347 75248
88261 56182
98982 47735
90574 62875
51228 53905
25218 4567
78201 22017
59613 68982
37239 43727
67620 9064...

output:

1
1

result:

ok correct (1 test case)

Test #12:

score: 0
Accepted
time: 80ms
memory: 44292kb

input:

1
200000 200000
89381 101645
141954 180063
180085 158544
12185 82120
161570 175869
36911 151360
49966 148400
135100 143084
145185 33970
82150 111213
93727 145916
42620 157053
26848 66273
178649 76101
5033 162413
173225 34259
30781 78979
9908 187256
87177 127185
7086 26040
178611 119947
198142 154140...

output:

446
20130 32981 16279 100762 32003 57295 118223 54774 85510 141905 137093 86280 60802 196484 101381 2649 98468 164985 91324 146553 178224 22919 849 7636 179355 5268 27569 18890 69407 96485 173038 147859 155815 166766 184301 47934 66381 12769 81678 893 14179 198426 181099 158753 125320 103167 195138 ...

result:

ok correct (1 test case)

Test #13:

score: 0
Accepted
time: 62ms
memory: 31108kb

input:

1
199809 199808
197381 136472
136472 160228
160228 128766
128766 197225
197225 160133
160133 105707
105707 66465
66465 199512
199512 185463
185463 176514
176514 175293
175293 178768
178768 158873
158873 199518
199518 161400
161400 172476
172476 188761
188761 197795
197795 152286
152286 177332
177332...

output:

446
171689 198734 123009 166219 189537 185622 100072 149905 128572 193842 122073 159953 186516 176986 191530 136472 183233 190183 191576 160824 188604 194460 124730 134556 137621 162382 183962 117053 164701 115691 185421 193395 198350 167488 85512 163716 175096 185086 193783 150325 190697 199024 181...

result:

ok correct (1 test case)

Test #14:

score: 0
Accepted
time: 34ms
memory: 3732kb

input:

200
961 1663
2 1
3 1
3 20
4 1
4 7
5 1
5 41
5 60
6 1
7 1
7 49
8 1
9 1
10 1
11 1
12 1
12 32
13 1
13 59
14 1
14 3
15 1
15 12
15 52
16 1
16 12
16 63
17 1
17 10
18 1
18 36
19 1
19 26
19 29
20 1
20 60
20 63
21 1
22 1
23 1
23 3
23 27
23 39
24 1
25 1
26 1
26 58
26 60
27 1
27 22
27 36
28 1
29 1
30 1
31 1
31 ...

output:

3
80 35 1
3
98 30 1
3
139 146 1
3
131 133 1
3
138 72 1
4
122 70 51 1
4
181 37 33 1
2
228 1
4
96 67 39 1
4
120 80 62 1
3
57 43 1
3
107 60 1
2
92 1
4
217 149 45 1
4
139 115 107 1
3
109 48 1
3
223 103 1
4
121 97 42 1
3
36 15 1
3
150 93 1
4
150 130 85 1
2
102 1
4
103 94 54 1
4
101 104 15 1
2
113 1
3
130...

result:

ok correct (200 test cases)

Test #15:

score: 0
Accepted
time: 31ms
memory: 26972kb

input:

1
160000 159999
1 2
2 3
3 4
4 5
5 6
6 7
7 8
8 9
9 10
10 11
11 12
12 13
13 14
14 15
15 16
16 17
17 18
18 19
19 20
20 21
21 22
22 23
23 24
24 25
25 26
26 27
27 28
28 29
29 30
30 31
31 32
32 33
33 34
34 35
35 36
36 37
37 38
38 39
39 40
40 41
41 42
42 43
43 44
44 45
45 46
46 47
47 48
48 49
49 50
50 51
5...

output:

2
2 1

result:

ok correct (1 test case)

Test #16:

score: 0
Accepted
time: 13ms
memory: 3660kb

input:

1
1000 499500
605 964
559 738
492 518
943 284
96 23
214 486
487 262
347 436
394 422
270 113
984 149
134 203
881 328
316 643
610 922
802 67
903 194
600 584
629 62
692 370
420 442
600 563
438 452
556 785
112 809
555 241
937 635
178 746
67 900
777 247
490 842
971 12
315 60
703 467
201 13
872 503
24 201...

output:

3
370 156 1

result:

ok correct (1 test case)

Test #17:

score: 0
Accepted
time: 30ms
memory: 3588kb

input:

4081
49 48
39 7
7 45
45 25
25 31
31 26
26 4
4 11
4 19
4 37
4 8
4 16
4 22
4 33
11 14
39 6
6 12
12 46
46 49
49 48
48 29
29 27
39 41
41 15
15 34
34 24
39 3
3 13
13 20
20 47
39 9
9 36
36 5
5 43
39 40
40 21
21 2
2 38
39 35
35 42
42 23
23 28
39 1
1 32
32 10
10 17
39 30
30 18
18 44
49 48
37 29
29 33
33 19
...

output:

3
7 39 1
3
29 37 1
2
44 1
3
36 43 1
3
37 16 1
3
46 43 1
2
28 1
2
34 1
3
39 21 1
3
11 13 1
2
43 1
3
7 19 1
3
8 28 1
3
6 14 1
3
30 48 1
2
5 1
3
43 37 1
2
4 1
2
8 1
3
9 30 1
3
8 23 1
3
35 21 1
3
6 19 1
3
19 4 1
3
17 35 1
3
2 3 1
2
26 1
3
39 47 1
2
33 1
3
25 2 1
3
6 7 1
3
41 44 1
2
42 1
3
14 28 1
3
41 3...

result:

ok correct (4081 test cases)