結果

問題 No.827 総神童数
ユーザー risujirohrisujiroh
提出日時 2019-05-03 21:29:56
言語 C++14
(gcc 12.3.0 + boost 1.83.0)
結果
AC  
実行時間 108 ms / 2,000 ms
コード長 3,231 bytes
コンパイル時間 1,859 ms
コンパイル使用メモリ 177,388 KB
実行使用メモリ 24,176 KB
最終ジャッジ日時 2024-06-10 06:27:02
合計ジャッジ時間 6,079 ms
ジャッジサーバーID
（参考情報） 		judge1 / judge4
このコードへのチャレンジ
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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 2 ms
6,812 KB
testcase_01 AC 2 ms
6,940 KB
testcase_02 AC 2 ms
6,940 KB
testcase_03 AC 2 ms
6,944 KB
testcase_04 AC 2 ms
6,940 KB
testcase_05 AC 2 ms
6,940 KB
testcase_06 AC 2 ms
6,940 KB
testcase_07 AC 2 ms
6,940 KB
testcase_08 AC 2 ms
6,940 KB
testcase_09 AC 106 ms
24,176 KB
testcase_10 AC 32 ms
10,112 KB
testcase_11 AC 4 ms
6,944 KB
testcase_12 AC 16 ms
6,940 KB
testcase_13 AC 78 ms
20,352 KB
testcase_14 AC 5 ms
6,940 KB
testcase_15 AC 31 ms
10,112 KB
testcase_16 AC 77 ms
18,060 KB
testcase_17 AC 104 ms
21,144 KB
testcase_18 AC 40 ms
11,776 KB
testcase_19 AC 105 ms
17,700 KB
testcase_20 AC 71 ms
13,748 KB
testcase_21 AC 47 ms
11,136 KB
testcase_22 AC 84 ms
14,720 KB
testcase_23 AC 2 ms
6,940 KB
testcase_24 AC 94 ms
16,072 KB
testcase_25 AC 65 ms
12,996 KB
testcase_26 AC 93 ms
16,028 KB
testcase_27 AC 55 ms
11,888 KB
testcase_28 AC 56 ms
11,776 KB
testcase_29 AC 45 ms
10,112 KB
testcase_30 AC 14 ms
6,944 KB
testcase_31 AC 33 ms
8,576 KB
testcase_32 AC 34 ms
8,448 KB
testcase_33 AC 108 ms
17,244 KB
testcase_34 AC 94 ms
16,056 KB
testcase_35 AC 33 ms
8,576 KB
testcase_36 AC 50 ms
10,880 KB
testcase_37 AC 65 ms
13,056 KB
testcase_38 AC 103 ms
17,112 KB
権限があれば一括ダウンロードができます
コンパイルメッセージ
main.cpp:11:10: warning: use of 'auto' in parameter declaration only available with '-std=c++20' or '-fconcepts'
   11 |   ModInt(auto x) : v(x >= 0 ? x % P : (P - -x % P) % P) {}
      |          ^~~~
main.cpp:38:9: warning: use of 'auto' in parameter declaration only available with '-std=c++20' or '-fconcepts'
   38 |   M pow(auto n) const {
      |         ^~~~
main.cpp:44:22: warning: use of 'auto' in parameter declaration only available with '-std=c++20' or '-fconcepts'
   44 |   friend M operator*(auto l, M r) { return M(l) *= r; }
      |                      ^~~~
main.cpp:45:22: warning: use of 'auto' in parameter declaration only available with '-std=c++20' or '-fconcepts'
   45 |   friend M operator/(auto l, M r) { return M(l) /= r; }
      |                      ^~~~
main.cpp:46:22: warning: use of 'auto' in parameter declaration only available with '-std=c++20' or '-fconcepts'
   46 |   friend M operator+(auto l, M r) { return M(l) += r; }
      |                      ^~~~
main.cpp:47:22: warning: use of 'auto' in parameter declaration only available with '-std=c++20' or '-fconcepts'
   47 |   friend M operator-(auto l, M r) { return M(l) -= r; }
      |                      ^~~~
main.cpp:50:26: warning: use of 'auto' in parameter declaration only available with '-std=c++20' or '-fconcepts'
   50 |   friend bool operator==(auto l, M r) { return M(l) == r; }
      |                          ^~~~
main.cpp:51:26: warning: use of 'auto' in parameter declaration only available with '-std=c++20' or '-fconcepts'
   51 |   friend bool operator!=(auto l, M r) { return !(l == r); }
      |                          ^~~~

ソースコード

diff # 

#include <bits/stdc++.h>
using namespace std;
using lint = long long;
template<class T = int> using V = vector<T>;
template<class T = int> using VV = V< V<T> >;

template<unsigned P> struct ModInt {
  using M = ModInt;
  unsigned v;
  ModInt() : v(0) {}
  ModInt(auto x) : v(x >= 0 ? x % P : (P - -x % P) % P) {}
  constexpr ModInt(unsigned v, int) : v(v) {}
  static constexpr unsigned p() { return P; }
  M operator+() const { return *this; }
  M operator-() const { return {v ? P - v : 0, 0}; }
  explicit operator bool() const noexcept { return v; }
  bool operator!() const noexcept { return !(bool) *this; }
  M operator*(M r) const { return M(*this) *= r; }
  M operator/(M r) const { return M(*this) /= r; }
  M operator+(M r) const { return M(*this) += r; }
  M operator-(M r) const { return M(*this) -= r; }
  bool operator==(M r) const { return v == r.v; }
  bool operator!=(M r) const { return !(*this == r); }
  M& operator*=(M r) { v = (uint64_t) v * r.v % P; return *this; }
  M& operator/=(M r) { return *this *= r.inv(); }
  M& operator+=(M r) { if ((v += r.v) >= P) v -= P; return *this; }
  M& operator-=(M r) { if ((v += P - r.v) >= P) v -= P; return *this; }
  M inv() const {
    int a = v, b = P, x = 1, u = 0;
    while (b) {
      int q = a / b;
      swap(a -= q * b, b);
      swap(x -= q * u, u);
    }
    assert(a == 1);
    return x;
  }
  M pow(auto n) const {
    if (n < 0) return pow(-n).inv();
    M res = 1;
    for (M a = *this; n; a *= a, n >>= 1) if (n & 1) res *= a;
    return res;
  }
  friend M operator*(auto l, M r) { return M(l) *= r; }
  friend M operator/(auto l, M r) { return M(l) /= r; }
  friend M operator+(auto l, M r) { return M(l) += r; }
  friend M operator-(auto l, M r) { return M(l) -= r; }
  friend ostream& operator<<(ostream& os, M r) { return os << r.v; }
  friend istream& operator>>(istream& is, M& r) { lint x; is >> x; r = x; return is; }
  friend bool operator==(auto l, M r) { return M(l) == r; }
  friend bool operator!=(auto l, M r) { return !(l == r); }
};
using Mint = ModInt<(unsigned) 1e9 + 7>;
V<Mint> fact, ifact, inv, powB;
void init(int n, int B = 2) {
  fact.resize(n + 1);
  fact[0] = 1;
  for (int i = 1; i <= n; ++i) {
    fact[i] = i * fact[i - 1];
  }
  ifact.resize(n + 1);
  ifact[n] = fact[n].inv();
  for (int i = n; i > 0; --i) {
    ifact[i - 1] = i * ifact[i];
  }
  inv.resize(n + 1);
  inv[1] = 1;
  for (int i = 2; i <= n; ++i) {
    int q = Mint::p() / i;
    inv[i] = -q * inv[Mint::p() - i * q];
  }
  powB.resize(n + 1);
  powB[0] = 1;
  for (int i = 0; i < n; ++i) {
    powB[i + 1] = powB[i] * B;
  }
}
Mint comb(int n, int r) {
  if (r < 0 or r > n) return 0;
  return fact[n] * ifact[r] * ifact[n - r];
}

int main() {
  cin.tie(nullptr); ios::sync_with_stdio(false);
  int n; cin >> n;
  init(n);
  VV<> g(n);
  for (int i = 0; i < n - 1; ++i) {
    int u, v; cin >> u >> v, --u, --v;
    g[u].push_back(v);
    g[v].push_back(u);
  }
  V<> d(n);
  auto dfs = [&](const auto& dfs, int v, int p) -> void {
    for (int w : g[v]) if (w != p) {
      d[w] = d[v] + 1;
      dfs(dfs, w, v);
    }
  };
  dfs(dfs, 0, -1);
  Mint res;
  for (int v = 0; v < n; ++v) {
    res += fact[n] * inv[d[v] + 1];
  }
  cout << res << '\n';
}
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