結果

問題 No.1473 おでぶなおばけさん
コンテスト
ユーザー stoq
提出日時 2021-04-09 21:49:54
言語 C++17
(gcc 13.3.0 + boost 1.87.0)
結果
AC  
実行時間 177 ms / 2,000 ms
コード長 5,318 bytes
コンパイル時間 3,464 ms
コンパイル使用メモリ 214,304 KB
最終ジャッジ日時 2025-01-20 14:09:25
ジャッジサーバーID
（参考情報） 		judge1 / judge2
このコードへのチャレンジ
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ファイルパターン 結果
sample AC * 2
other AC * 47
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 # 

#define MOD_TYPE 1

#pragma region Macros

#include <bits/stdc++.h>
using namespace std;

#if 0
#include <boost/multiprecision/cpp_int.hpp>
#include <boost/multiprecision/cpp_dec_float.hpp>
using Int = boost::multiprecision::cpp_int;
using lld = boost::multiprecision::cpp_dec_float_100;
#endif
#if 1
#pragma GCC target("avx2")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#endif
using ll = long long int;
using ld = long double;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
using pld = pair<ld, ld>;
template <typename Q_type>
using smaller_queue = priority_queue<Q_type, vector<Q_type>, greater<Q_type>>;

constexpr ll MOD = (MOD_TYPE == 1 ? (ll)(1e9 + 7) : 998244353);
constexpr int INF = (int)1e9 + 10;
constexpr ll LINF = (ll)4e18;
constexpr ld PI = acos(-1.0);
constexpr ld EPS = 1e-9;
constexpr int Dx[] = {0, 0, -1, 1, -1, 1, -1, 1, 0};
constexpr int Dy[] = {1, -1, 0, 0, -1, -1, 1, 1, 0};

#define REP(i, m, n) for (ll i = m; i < (ll)(n); ++i)
#define rep(i, n) REP(i, 0, n)
#define REPI(i, m, n) for (int i = m; i < (int)(n); ++i)
#define repi(i, n) REPI(i, 0, n)
#define MP make_pair
#define MT make_tuple
#define YES(n) cout << ((n) ? "YES" : "NO") << "\n"
#define Yes(n) cout << ((n) ? "Yes" : "No") << "\n"
#define possible(n) cout << ((n) ? "possible" : "impossible") << "\n"
#define Possible(n) cout << ((n) ? "Possible" : "Impossible") << "\n"
#define all(v) v.begin(), v.end()
#define NP(v) next_permutation(all(v))
#define dbg(x) cerr << #x << ":" << x << "\n";

struct io_init
{
  io_init()
  {
    cin.tie(0);
    ios::sync_with_stdio(false);
    cout << setprecision(30) << setiosflags(ios::fixed);
  };
} io_init;
template <typename T>
inline bool chmin(T &a, T b)
{
  if (a > b)
  {
    a = b;
    return true;
  }
  return false;
}
template <typename T>
inline bool chmax(T &a, T b)
{
  if (a < b)
  {
    a = b;
    return true;
  }
  return false;
}
inline ll CEIL(ll a, ll b)
{
  return (a + b - 1) / b;
}
template <typename A, size_t N, typename T>
inline void Fill(A (&array)[N], const T &val)
{
  fill((T *)array, (T *)(array + N), val);
}
template <typename T, typename U>
constexpr istream &operator>>(istream &is, pair<T, U> &p) noexcept
{
  is >> p.first >> p.second;
  return is;
}
template <typename T, typename U>
constexpr ostream &operator<<(ostream &os, pair<T, U> &p) noexcept
{
  os << p.first << " " << p.second;
  return os;
}
#pragma endregion

// --------------------------------------

struct UnionFind
{
public:
  UnionFind() : _n(0) {}
  UnionFind(int n) : _n(n), parent_or_size(n, -1) {}

  int unite(int a, int b)
  {
    assert(0 <= a && a < _n);
    assert(0 <= b && b < _n);
    int x = root(a), y = root(b);
    if (x == y)
      return x;
    if (-parent_or_size[x] < -parent_or_size[y])
      swap(x, y);
    parent_or_size[x] += parent_or_size[y];
    parent_or_size[y] = x;
    return x;
  }

  bool same(int a, int b)
  {
    assert(0 <= a && a < _n);
    assert(0 <= b && b < _n);
    return root(a) == root(b);
  }

  int root(int a)
  {
    assert(0 <= a && a < _n);
    if (parent_or_size[a] < 0)
      return a;
    return parent_or_size[a] = root(parent_or_size[a]);
  }

  int size(int a)
  {
    assert(0 <= a && a < _n);
    return -parent_or_size[root(a)];
  }

  vector<vector<int>> groups()
  {
    vector<int> leader_buf(_n), group_size(_n);
    for (int i = 0; i < _n; i++)
    {
      leader_buf[i] = root(i);
      group_size[leader_buf[i]]++;
    }
    vector<vector<int>> result(_n);
    for (int i = 0; i < _n; i++)
    {
      result[i].reserve(group_size[i]);
    }
    for (int i = 0; i < _n; i++)
    {
      result[leader_buf[i]].push_back(i);
    }
    result.erase(
        remove_if(result.begin(), result.end(),
                  [&](const vector<int> &v) { return v.empty(); }),
        result.end());
    return result;
  }

private:
  int _n;
  vector<int> parent_or_size;
};

// 01BFS
template <typename T>
struct BFS
{
  vector<int> d;
  vector<vector<pair<int, T>>> E;
  BFS(int V, T INF) : d(V, INF), E(V) {}

  void add_edge(int u, int v, bool c, bool directed = true)
  {
    E[u].push_back({v, c});
    if (!directed)
      E[v].push_back({u, c});
  }

  void calc(int s)
  {
    d[s] = T(0);
    deque<int> que;
    que.push_front(s);
    while (!que.empty())
    {
      int u = que.front();
      que.pop_front();
      for (auto [v, c] : E[u])
      {
        if (d[v] <= d[u] + c)
          continue;
        d[v] = d[u] + c;
        if (!c)
          que.push_front(v);
        else
          que.push_back(v);
      }
    }
  }
};

void solve()
{
  int n, m;
  cin >> n >> m;
  vector<int> s(m), t(m), d(m);
  rep(i, m)
  {
    cin >> s[i] >> t[i] >> d[i];
    s[i]--, t[i]--;
  }

  auto simulate = [&](ll x) {
    UnionFind uf(n);
    rep(i, m)
    {
      if (d[i] >= x)
        uf.unite(s[i], t[i]);
    }
    return uf.same(0, n - 1);
  };

  auto binary_search = [&]() {
    int lo = 0, hi = 1e9 + 10;
    while (hi - lo > 1)
    {
      int mi = (lo + hi) / 2;
      if (simulate(mi))
        lo = mi;
      else
        hi = mi;
    }
    return lo;
  };

  int W = binary_search();

  BFS<int> bfs(n, INF);
  rep(i, m)
  {
    if (d[i] >= W)
      bfs.add_edge(s[i], t[i], 1, false);
  }
  bfs.calc(0);
  cout << W << " " << bfs.d[n - 1] << "\n";
}

int main()
{
  solve();
}
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