結果

問題 No.1300 Sum of Inversions
ユーザー stoqstoq
提出日時 2020-11-28 06:51:42
言語 C++17
(gcc 12.3.0 + boost 1.83.0)
結果
AC  
実行時間 819 ms / 2,000 ms
コード長 6,469 bytes
コンパイル時間 2,443 ms
コンパイル使用メモリ 222,640 KB
実行使用メモリ 35,060 KB
最終ジャッジ日時 2023-10-09 23:31:26
合計ジャッジ時間 22,399 ms
ジャッジサーバーID
（参考情報） 		judge12 / judge15
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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
4,352 KB
testcase_01 AC 2 ms
4,356 KB
testcase_02 AC 1 ms
4,348 KB
testcase_03 AC 609 ms
31,356 KB
testcase_04 AC 585 ms
31,072 KB
testcase_05 AC 466 ms
20,796 KB
testcase_06 AC 672 ms
33,040 KB
testcase_07 AC 670 ms
32,424 KB
testcase_08 AC 724 ms
33,716 KB
testcase_09 AC 751 ms
33,688 KB
testcase_10 AC 369 ms
19,340 KB
testcase_11 AC 392 ms
19,572 KB
testcase_12 AC 596 ms
31,084 KB
testcase_13 AC 558 ms
30,984 KB
testcase_14 AC 819 ms
34,852 KB
testcase_15 AC 728 ms
33,476 KB
testcase_16 AC 610 ms
31,744 KB
testcase_17 AC 352 ms
19,080 KB
testcase_18 AC 430 ms
20,060 KB
testcase_19 AC 520 ms
29,840 KB
testcase_20 AC 536 ms
30,036 KB
testcase_21 AC 520 ms
30,136 KB
testcase_22 AC 466 ms
20,868 KB
testcase_23 AC 690 ms
33,044 KB
testcase_24 AC 475 ms
21,388 KB
testcase_25 AC 383 ms
19,812 KB
testcase_26 AC 385 ms
19,740 KB
testcase_27 AC 426 ms
20,536 KB
testcase_28 AC 779 ms
34,004 KB
testcase_29 AC 504 ms
30,016 KB
testcase_30 AC 735 ms
33,588 KB
testcase_31 AC 452 ms
21,184 KB
testcase_32 AC 480 ms
21,380 KB
testcase_33 AC 174 ms
22,752 KB
testcase_34 AC 189 ms
22,416 KB
testcase_35 AC 383 ms
35,060 KB
testcase_36 AC 389 ms
35,032 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 2

#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 double PI = acos(-1.0);
constexpr double EPS = 1e-7;
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

#pragma region mint
template <int MOD>
struct Fp
{
  long long val;

  constexpr Fp(long long v = 0) noexcept : val(v % MOD)
  {
    if (val < 0)
      v += MOD;
  }

  constexpr int getmod()
  {
    return MOD;
  }

  constexpr Fp operator-() const noexcept
  {
    return val ? MOD - val : 0;
  }

  constexpr Fp operator+(const Fp &r) const noexcept
  {
    return Fp(*this) += r;
  }

  constexpr Fp operator-(const Fp &r) const noexcept
  {
    return Fp(*this) -= r;
  }

  constexpr Fp operator*(const Fp &r) const noexcept
  {
    return Fp(*this) *= r;
  }

  constexpr Fp operator/(const Fp &r) const noexcept
  {
    return Fp(*this) /= r;
  }

  constexpr Fp &operator+=(const Fp &r) noexcept
  {
    val += r.val;
    if (val >= MOD)
      val -= MOD;
    return *this;
  }

  constexpr Fp &operator-=(const Fp &r) noexcept
  {
    val -= r.val;
    if (val < 0)
      val += MOD;
    return *this;
  }

  constexpr Fp &operator*=(const Fp &r) noexcept
  {
    val = val * r.val % MOD;
    if (val < 0)
      val += MOD;
    return *this;
  }

  constexpr Fp &operator/=(const Fp &r) noexcept
  {
    long long a = r.val, b = MOD, u = 1, v = 0;
    while (b)
    {
      long long t = a / b;
      a -= t * b;
      swap(a, b);
      u -= t * v;
      swap(u, v);
    }
    val = val * u % MOD;
    if (val < 0)
      val += MOD;
    return *this;
  }

  constexpr bool operator==(const Fp &r) const noexcept
  {
    return this->val == r.val;
  }

  constexpr bool operator!=(const Fp &r) const noexcept
  {
    return this->val != r.val;
  }

  friend constexpr ostream &operator<<(ostream &os, const Fp<MOD> &x) noexcept
  {
    return os << x.val;
  }

  friend constexpr istream &operator>>(istream &is, Fp<MOD> &x) noexcept
  {
    return is >> x.val;
  }
};

Fp<MOD> modpow(const Fp<MOD> &a, long long n) noexcept
{
  if (n == 0)
    return 1;
  auto t = modpow(a, n / 2);
  t = t * t;
  if (n & 1)
    t = t * a;
  return t;
}

using mint = Fp<MOD>;
#pragma endregion

template <typename T>
struct SegmentTree
{
  using Fn = function<T(T, T)>;
  int N;
  vector<T> dat;
  T ti;
  Fn f;

  SegmentTree() {}
  SegmentTree(int n, Fn f, T ti) : f(f), ti(ti)
  {
    N = 1;
    while (N < n)
      N *= 2;
    dat.assign(2 * N - 1, ti);
  }
  SegmentTree(const vector<T> &v, Fn f, T ti) : f(f), ti(ti)
  {
    N = 1;
    int sz = v.size();
    while (N < sz)
      N *= 2;
    dat.resize(2 * N - 1);
    for (int i = 0; i < N; ++i)
      dat[i + N - 1] = (i < sz ? v[i] : ti);
    for (int i = N - 2; i >= 0; --i)
      dat[i] = f(dat[i * 2 + 1], dat[i * 2 + 2]);
  }

  void update(int k, T a)
  {
    k += N - 1;
    dat[k] = a;
    while (k > 0)
    {
      k = (k - 1) / 2;
      dat[k] = f(dat[k * 2 + 1], dat[k * 2 + 2]);
    }
  }

  T get(int k) { return dat[k + N - 1]; }

  void add(int k, T a) { update(k, f(get(k), a)); }

  T query(int l, int r)
  {
    T vl = ti, vr = ti;
    for (l += (N - 1), r += (N - 1); l < r; l >>= 1, r >>= 1)
    {
      if ((l & 1) == 0)
        vl = f(vl, dat[l]);
      if ((r & 1) == 0)
        vr = f(vr, dat[--r]);
    }
    return f(vl, vr);
  }
  T query_all() { return dat[0]; }

  void display()
  {
    for (int i = 0; i < N; i++)
      cerr << get(i) << " ";
    cerr << "\n";
  }
};

void solve()
{
  ll n;
  cin >> n;
  map<ll, int> pos;
  vector<ll> a(n);
  vector<mint> ma(n);
  rep(i, n)
  {
    cin >> a[i];
    pos[a[i]] = 0;
    ma[i] = a[i] % MOD;
  }
  int z = 0;
  for (auto &&[k, v] : pos)
    v = z++;
  auto f = [](pair<mint, ll> p, pair<mint, ll> q) {
    return MP(p.first + q.first, p.second + q.second);
  };
  SegmentTree<pair<mint, ll>> L(n, f, MP(0, 0));
  SegmentTree<pair<mint, ll>> R(n, f, MP(0, 0));
  rep(i, n)
  {
    R.add(pos[a[i]], {ma[i], 1});
  }
  mint ans = 0;
  rep(i, n)
  {
    R.add(pos[a[i]], {-ma[i], -1});
    auto [vl, cl] = L.query(pos[a[i]] + 1, n);
    auto [vr, cr] = R.query(0, pos[a[i]]);
    ans += vl * cr + vr * cl + ma[i] * cl * cr;
    L.add(pos[a[i]], {ma[i], 1});
  }
  cout << ans << "\n";
}

int main()
{
  solve();
}
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