結果

問題 No.1813 Magical Stones
ユーザー stoqstoq
提出日時 2022-01-14 21:30:25
言語 C++17
(gcc 12.3.0 + boost 1.83.0)
結果
AC  
実行時間 186 ms / 2,000 ms
コード長 6,731 bytes
コンパイル時間 4,995 ms
コンパイル使用メモリ 298,964 KB
実行使用メモリ 29,164 KB
最終ジャッジ日時 2024-11-20 07:56:59
合計ジャッジ時間 10,070 ms
ジャッジサーバーID
（参考情報） 		judge4 / judge2
このコードへのチャレンジ
（要ログイン）

テストケース

テストケース表示
入力 結果 実行時間
実行使用メモリ
testcase_00 AC 33 ms
14,936 KB
testcase_01 AC 34 ms
14,976 KB
testcase_02 AC 33 ms
14,912 KB
testcase_03 AC 43 ms
24,080 KB
testcase_04 AC 32 ms
14,976 KB
testcase_05 AC 33 ms
15,104 KB
testcase_06 AC 34 ms
15,488 KB
testcase_07 AC 34 ms
14,976 KB
testcase_08 AC 35 ms
15,092 KB
testcase_09 AC 33 ms
15,104 KB
testcase_10 AC 33 ms
15,100 KB
testcase_11 AC 54 ms
19,200 KB
testcase_12 AC 34 ms
14,976 KB
testcase_13 AC 35 ms
14,976 KB
testcase_14 AC 42 ms
24,072 KB
testcase_15 AC 186 ms
29,148 KB
testcase_16 AC 186 ms
29,132 KB
testcase_17 AC 175 ms
28,828 KB
testcase_18 AC 177 ms
29,140 KB
testcase_19 AC 179 ms
29,148 KB
testcase_20 AC 175 ms
29,164 KB
testcase_21 AC 177 ms
29,128 KB
testcase_22 AC 174 ms
29,164 KB
testcase_23 AC 180 ms
29,144 KB
testcase_24 AC 35 ms
15,068 KB
testcase_25 AC 44 ms
17,536 KB
testcase_26 AC 38 ms
16,000 KB
testcase_27 AC 124 ms
25,504 KB
testcase_28 AC 134 ms
24,040 KB
testcase_29 AC 149 ms
26,008 KB
testcase_30 AC 144 ms
25,276 KB
testcase_31 AC 172 ms
28,616 KB
testcase_32 AC 35 ms
14,976 KB
testcase_33 AC 34 ms
15,104 KB
testcase_34 AC 36 ms
15,356 KB
testcase_35 AC 42 ms
15,744 KB
testcase_36 AC 36 ms
15,488 KB
testcase_37 AC 56 ms
17,052 KB
testcase_38 AC 45 ms
21,376 KB
testcase_39 AC 112 ms
25,872 KB
testcase_40 AC 35 ms
15,488 KB
testcase_41 AC 36 ms
15,232 KB
testcase_42 AC 42 ms
15,744 KB
testcase_43 AC 41 ms
15,872 KB
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

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

#include <atcoder/all>
//#include <atcoder/modint>
//#include <atcoder/lazysegtree>
//#include <atcoder/segtree>

using namespace atcoder;

#if 0
#include <boost/multiprecision/cpp_dec_float.hpp>
#include <boost/multiprecision/cpp_int.hpp>
using Int = boost::multiprecision::cpp_int;
using lld = boost::multiprecision::cpp_dec_float_100;
#endif

#if 1
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tag_and_trait.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/rope>
using namespace __gnu_pbds;
using namespace __gnu_cxx;
template <typename T>
using extset =
    tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
#endif

#if 0
#pragma GCC target("avx2")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#endif

#pragma region Macros

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>>;

#if MOD_TYPE == 1
constexpr ll MOD = ll(1e9 + 7);
#else
#if MOD_TYPE == 2
constexpr ll MOD = 998244353;
#else
constexpr ll MOD = 1000003;
#endif
#endif

using mint = static_modint<MOD>;
constexpr int INF = (int)1e9 + 10;
constexpr ll LINF = (ll)4e18;
constexpr double PI = acos(-1.0);
constexpr double EPS = 1e-11;
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 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";
#define UNIQUE(v) v.erase(unique(all(v)), v.end())

struct io_init {
  io_init() {
    cin.tie(nullptr);
    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>
vector<T> compress(vector<T> &v) {
  vector<T> val = v;
  sort(all(val)), val.erase(unique(all(val)), val.end());
  for (auto &&vi : v) vi = lower_bound(all(val), vi) - val.begin();
  return 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;
}
ostream &operator<<(ostream &os, mint m) {
  os << m.val();
  return os;
}
ostream &operator<<(ostream &os, modint m) {
  os << m.val();
  return os;
}
template <typename T>
constexpr istream &operator>>(istream &is, vector<T> &v) noexcept {
  for (int i = 0; i < v.size(); i++) is >> v[i];
  return is;
}
template <typename T>
constexpr ostream &operator<<(ostream &os, vector<T> &v) noexcept {
  for (int i = 0; i < v.size(); i++)
    os << v[i] << (i + 1 == v.size() ? "" : " ");
  return os;
}

random_device seed_gen;
mt19937_64 engine(seed_gen());

struct BiCoef {
  vector<mint> fact_, inv_, finv_;
  BiCoef(int n) noexcept : fact_(n, 1), inv_(n, 1), finv_(n, 1) {
    fact_.assign(n, 1), inv_.assign(n, 1), finv_.assign(n, 1);
    for (int i = 2; i < n; i++) {
      fact_[i] = fact_[i - 1] * i;
      inv_[i] = -inv_[MOD % i] * (MOD / i);
      finv_[i] = finv_[i - 1] * inv_[i];
    }
  }
  mint C(ll n, ll k) const noexcept {
    if (n < k || n < 0 || k < 0) return 0;
    return fact_[n] * finv_[k] * finv_[n - k];
  }
  mint P(ll n, ll k) const noexcept { return C(n, k) * fact_[k]; }
  mint H(ll n, ll k) const noexcept { return C(n + k - 1, k); }
  mint Ch1(ll n, ll k) const noexcept {
    if (n < 0 || k < 0) return 0;
    mint res = 0;
    for (int i = 0; i < n; i++)
      res += C(n, i) * mint(n - i).pow(k) * (i & 1 ? -1 : 1);
    return res;
  }
  mint fact(ll n) const noexcept {
    if (n < 0) return 0;
    return fact_[n];
  }
  mint inv(ll n) const noexcept {
    if (n < 0) return 0;
    return inv_[n];
  }
  mint finv(ll n) const noexcept {
    if (n < 0) return 0;
    return finv_[n];
  }
};

BiCoef bc(1000010);

#pragma endregion

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

struct SCC {
  int V;
  vector<vector<int>> G, Gr;
  vector<int> comp, order, used;

  SCC(int V_) : V(V_), G(V_), Gr(V_), comp(V_, -1), used(V_) {}

  void add_edge(int a, int b) {
    G[a].emplace_back(b);
    Gr[b].emplace_back(a);
  }

  // 番号はトポロジカル順
  int operator[](int k) { return comp[k]; }

  void dfs(int idx) {
    if (used[idx]) return;
    used[idx] = true;
    for (int to : G[idx]) dfs(to);
    order.emplace_back(idx);
  }

  void rdfs(int idx, int cnt) {
    if (comp[idx] != -1) return;
    comp[idx] = cnt;
    for (int to : Gr[idx]) rdfs(to, cnt);
  }

  // del_mul が false の場合高速になるが多重辺が生える
  vector<vector<int>> build(bool del_mul = true) {
    vector<vector<int>> res;
    for (int i = 0; i < G.size(); i++) dfs(i);
    reverse(begin(order), end(order));
    int ptr = 0;
    for (int i : order)
      if (comp[i] == -1) rdfs(i, ptr), ptr++;

    res.resize(ptr);
    for (int i = 0; i < G.size(); i++) {
      for (auto &to : G[i]) {
        int x = comp[i], y = comp[to];
        if (x == y) continue;
        res[x].push_back(y);
      }
    }
    if (del_mul) {
      for (auto &&v : res) {
        sort(begin(v), end(v));
        auto itr = unique(begin(v), end(v));
        v.erase(itr, v.end());
      }
    }
    return res;
  }
};

void solve() {
  int n, m;
  cin >> n >> m;
  SCC G(n);
  rep(i, m) {
    int a, b;
    cin >> a >> b;
    a--, b--;
    G.add_edge(a, b);
  }
  auto E = G.build();
  n = E.size();
  if (n == 1) {
    cout << 0 << "\n";
    return;
  }
  vector<int> in(n, 0), out(n, 0);
  rep(i, n) {
    for (auto j : E[i]) {
      in[i]++, out[j]++;
    }
  }
  int x = 0, y = 0;
  rep(i, n) {
    if (in[i] == 0) x++;
    if (out[i] == 0) y++;
  }
  cout << max(x, y) << "\n";
}

int main() { solve(); }
0