#827635 (C++17) No.2170 Left Addition Machine

• 問題: No.2170 Left Addition Machine
• ユーザー: emthrm
• 提出日時: 2022-12-22 15:49:00
• 言語: C++17 (gcc 13.3.0 + boost 1.87.0)
• 結果: WA
• 実行時間: -
• コード長: 8,031 bytes
• コンパイル時間: 2,658 ms
• コンパイル使用メモリ: 212,556 KB
• 最終ジャッジ日時: 2025-02-09 18:22:30
• ジャッジサーバーID （参考情報）: judge5 / judge4

ファイルパターン	結果
other	AC * 15 WA * 54

ソースコード

#define _USE_MATH_DEFINES
#include <bits/stdc++.h>
using namespace std;
#define FOR(i,m,n) for(int i=(m);i<(n);++i)
#define REP(i,n) FOR(i,0,n)
#define ALL(v) (v).begin(),(v).end()
using ll = long long;
constexpr int INF = 0x3f3f3f3f;
constexpr long long LINF = 0x3f3f3f3f3f3f3f3fLL;
constexpr double EPS = 1e-8;
constexpr int MOD = 998244353;
// constexpr int MOD = 1000000007;
constexpr int DY4[]{1, 0, -1, 0}, DX4[]{0, -1, 0, 1};
constexpr int DY8[]{1, 1, 0, -1, -1, -1, 0, 1};
constexpr int DX8[]{0, -1, -1, -1, 0, 1, 1, 1};
template <typename T, typename U>
inline bool chmax(T& a, U b) { return a < b ? (a = b, true) : false; }
template <typename T, typename U>
inline bool chmin(T& a, U b) { return a > b ? (a = b, true) : false; }
struct IOSetup {
  IOSetup() {
    std::cin.tie(nullptr);
    std::ios_base::sync_with_stdio(false);
    std::cout << fixed << setprecision(20);
  }
} iosetup;

template <int M>
struct MInt {
  unsigned int v;
  MInt() : v(0) {}
  MInt(const long long x) : v(x >= 0 ? x % M : x % M + M) {}
  static constexpr int get_mod() { return M; }
  static void set_mod(const int divisor) { assert(divisor == M); }
  static void init(const int x = 10000000) {
    inv(x, true);
    fact(x);
    fact_inv(x);
  }
  static MInt inv(const int n, const bool init = false) {
    // assert(0 <= n && n < M && std::__gcd(n, M) == 1);
    static std::vector<MInt> inverse{0, 1};
    const int prev = inverse.size();
    if (n < prev) {
      return inverse[n];
    } else if (init) {
      // "n!" and "M" must be disjoint.
      inverse.resize(n + 1);
      for (int i = prev; i <= n; ++i) {
        inverse[i] = -inverse[M % i] * (M / i);
      }
      return inverse[n];
    }
    int u = 1, v = 0;
    for (unsigned int a = n, b = M; b;) {
      const unsigned int q = a / b;
      std::swap(a -= q * b, b);
      std::swap(u -= q * v, v);
    }
    return u;
  }
  static MInt fact(const int n) {
    static std::vector<MInt> factorial{1};
    const int prev = factorial.size();
    if (n >= prev) {
      factorial.resize(n + 1);
      for (int i = prev; i <= n; ++i) {
        factorial[i] = factorial[i - 1] * i;
      }
    }
    return factorial[n];
  }
  static MInt fact_inv(const int n) {
    static std::vector<MInt> f_inv{1};
    const int prev = f_inv.size();
    if (n >= prev) {
      f_inv.resize(n + 1);
      f_inv[n] = inv(fact(n).v);
      for (int i = n; i > prev; --i) {
        f_inv[i - 1] = f_inv[i] * i;
      }
    }
    return f_inv[n];
  }
  static MInt nCk(const int n, const int k) {
    if (n < 0 || n < k || k < 0) return 0;
    return fact(n) * (n - k < k ? fact_inv(k) * fact_inv(n - k) :
                                  fact_inv(n - k) * fact_inv(k));
  }
  static MInt nPk(const int n, const int k) {
    return n < 0 || n < k || k < 0 ? 0 : fact(n) * fact_inv(n - k);
  }
  static MInt nHk(const int n, const int k) {
    return n < 0 || k < 0 ? 0 : (k == 0 ? 1 : nCk(n + k - 1, k));
  }
  static MInt large_nCk(long long n, const int k) {
    if (n < 0 || n < k || k < 0) return 0;
    inv(k, true);
    MInt res = 1;
    for (int i = 1; i <= k; ++i) {
      res *= inv(i) * n--;
    }
    return res;
  }
  MInt pow(long long exponent) const {
    MInt res = 1, tmp = *this;
    for (; exponent > 0; exponent >>= 1) {
      if (exponent & 1) res *= tmp;
      tmp *= tmp;
    }
    return res;
  }
  MInt& operator+=(const MInt& x) {
    if (static_cast<int>(v += x.v) >= M) v -= M;
    return *this;
  }
  MInt& operator-=(const MInt& x) {
    if (static_cast<int>(v += M - x.v) >= M) v -= M;
    return *this;
  }
  MInt& operator*=(const MInt& x) {
    v = static_cast<unsigned long long>(v) * x.v % M;
    return *this;
  }
  MInt& operator/=(const MInt& x) { return *this *= inv(x.v); }
  bool operator==(const MInt& x) const { return v == x.v; }
  bool operator!=(const MInt& x) const { return v != x.v; }
  bool operator<(const MInt& x) const { return v < x.v; }
  bool operator<=(const MInt& x) const { return v <= x.v; }
  bool operator>(const MInt& x) const { return v > x.v; }
  bool operator>=(const MInt& x) const { return v >= x.v; }
  MInt& operator++() {
    if (static_cast<int>(++v) == M) v = 0;
    return *this;
  }
  MInt operator++(int) {
    const MInt res = *this;
    ++*this;
    return res;
  }
  MInt& operator--() {
    v = (v == 0 ? M - 1 : v - 1);
    return *this;
  }
  MInt operator--(int) {
    const MInt res = *this;
    --*this;
    return res;
  }
  MInt operator+() const { return *this; }
  MInt operator-() const { return MInt(v ? M - v : 0); }
  MInt operator+(const MInt& x) const { return MInt(*this) += x; }
  MInt operator-(const MInt& x) const { return MInt(*this) -= x; }
  MInt operator*(const MInt& x) const { return MInt(*this) *= x; }
  MInt operator/(const MInt& x) const { return MInt(*this) /= x; }
  friend std::ostream& operator<<(std::ostream& os, const MInt& x) {
    return os << x.v;
  }
  friend std::istream& operator>>(std::istream& is, MInt& x) {
    long long v;
    is >> v;
    x = MInt(v);
    return is;
  }
};
using ModInt = MInt<MOD>;

struct Mo {
  explicit Mo(const std::vector<int>& ls, const std::vector<int>& rs)
      : n(ls.size()), ptr(0), nl(0), nr(0), ls(ls), rs(rs) {
    const int width = std::round(std::sqrt(n));
    order.resize(n);
    std::iota(order.begin(), order.end(), 0);
    std::sort(order.begin(), order.end(),
              [&ls, &rs, width](const int a, const int b) -> bool {
                  if (ls[a] / width != ls[b] / width) return ls[a] < ls[b];
                  return (ls[a] / width) & 1 ? rs[a] < rs[b] : rs[a] > rs[b];
              });
  }

  int process() {
    if (ptr == n) return -1;
    const int id = order[ptr++];
    while (ls[id] < nl) add(--nl);
    while (nr < rs[id]) add(nr++);
    while (nl < ls[id]) del(nl++);
    while (rs[id] < nr) del(--nr);
    return id;
  }

  void add(const int idx) const;

  void del(const int idx) const;

 private:
  const int n;
  int ptr, nl, nr;
  std::vector<int> ls, rs, order;
};

int len;
ModInt v = 0, sum = 0, nxt = 0;
vector<int> b;
vector<ModInt> fib;

void Mo::add(const int idx) const {
  if (idx + 1 == nr) {
    v += fib[nr - nl - 1] * b[idx];
    nxt += 1LL * b[idx] * (nr - nl - 1);
  } else {
    v += nxt + b[idx];
    nxt += sum;
  }
  sum += b[idx];
  // REP(i, b.size()) cout << b[i] << " \n"[i + 1 == b.size()];
  // cout << nl << ' ' << nr << ": " << v << ' ' << sum << ' ' << nxt << '\n';
}

void Mo::del(const int idx) const {
  if (idx == nr) {
    v -= fib[nr - nl] * b[idx];
    nxt -= 1LL * b[idx] * (nr - nl);
    sum -= b[idx];
  } else {
    sum -= b[idx];
    nxt -= sum;
    v -= nxt + b[idx];
  }
  // REP(i, b.size()) cout << b[i] << " \n"[i + 1 == b.size()];
  // cout << nl << ' ' << nr << ": " << v << ' ' << sum << ' ' << nxt << '\n';
}

int main() {
  int n, q; cin >> n >> q;
  vector<int> a(n), l(q), r(q);
  REP(i, n) cin >> a[i];
  REP(i, q) cin >> l[i] >> r[i], --l[i], --r[i];
  vector<vector<int>> queries(n);
  REP(i, q) queries[r[i]].emplace_back(i);
  fib.assign(n, 1);
  if (n > 2) fib[2] = 2;
  FOR(i, 3, n) fib[i] = fib[i - 1] + fib[i - 2] + fib[i - 3];
  vector<ModInt> ans(q, 0);
  for (int i = n - 1; i >= 0;) {
    int j = i;
    while (j > 0 && a[j - 1] < a[j]) --j;
    vector<int> ls, rs, ids;
    FOR(k, j, i + 1) {
      for (const int id : queries[k]) {
        ls.emplace_back(max(l[id], j) - j);
        rs.emplace_back(r[id] - j + 1);
        ids.emplace_back(id);
      }
    }
    if (!ls.empty()) {
      len = i - j + 1;
      v = sum = nxt = 0;
      b.resize(len);
      copy(next(a.begin(), j), next(a.begin(), i + 1), b.begin());
      Mo mo(ls, rs);
      while (true) {
        const int id = mo.process();
        if (id == -1) break;
        ans[ids[id]] = v;
      }
    }
    // for (const int id : queries[i]) {
    //   for (int fib_index = 0, p = max(j, l[id]); p <= i; ++fib_index, ++p) {
    //     ans[id] += fib[fib_index] * a[p];
    //   }
    // }
    i = j - 1;
  }
  REP(i, q) cout << ans[i] << '\n';
  return 0;
}