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mo_with_updates.hpp

SECTIONData Structure INCLUDEnoya/mo_with_updates.hpp

把区间询问与单点修改一起按三维 Mo 顺序处理;适合可增删元素且可前进、回退修改的离线题。

Complexity: Time: O((N + Q) N^(2/3)) range/time moves with standard blocking. Space: O(N + Q).

跳到代码 · GitHub ↗

Implementation

当前头文件,省略 include guard;依赖见 #include

/// @complexity Time: O((N + Q) N^(2/3)) range/time moves with standard blocking.
/// Space: O(N + Q).

#include <algorithm>
#include <cassert>
#include <cmath>
#include <numeric>
#include <tuple>
#include <vector>

namespace noya {

/// @brief Three-dimensional Mo scheduler for offline range queries mixed with
/// point updates; callbacks own the array and aggregate state.
struct mo_with_updates {
  struct query {
    int l = 0;
    int r = 0;
    int t = 0;
  };

  int n = 0;
  int nu = 0;
  std::vector<query> qs;

  mo_with_updates() = default;
  explicit mo_with_updates(int n_) : n(n_) { assert(n >= 0); }

  /// @brief Record one update in chronological order and return its id.
  int add_update() { return nu++; }

  /// @brief Append [l, r) at the current update time and return its id.
  int add_query(int l, int r) {
    assert(0 <= l && l <= r && r <= n);
    int id = int(qs.size());
    qs.push_back({l, r, nu});
    return id;
  }

  /// @brief Process queries while moving a range and time cursor. The update
  /// callbacks receive (update_id, current_left, current_right).
  template <class AddLeft, class AddRight, class RemoveLeft, class RemoveRight,
            class ApplyUpdate, class RollbackUpdate, class Answer>
  void run(AddLeft al, AddRight ar, RemoveLeft dl,
           RemoveRight dr, ApplyUpdate ap,
           RollbackUpdate un, Answer ans) const {
    if (qs.empty()) {
      return;
    }
    int bs = std::max(1, int(std::pow(std::max(1, n), 2.0 / 3.0)));
    std::vector<int> ord(qs.size());
    std::iota(ord.begin(), ord.end(), 0);
    std::sort(ord.begin(), ord.end(), [&](int arr, int B) {
      const query &a = qs[arr];
      const query &b = qs[B];
      int ba = a.l / bs;
      int bb = b.l / bs;
      if (ba != bb) {
        return ba < bb;
      }
      int ra = a.r / bs;
      int rb = b.r / bs;
      if (ra != rb) {
        return (ba & 1) ? ra > rb : ra < rb;
      }
      return ((ba ^ ra) & 1) ? a.t > b.t : a.t < b.t;
    });

    int l = 0;
    int r = 0;
    int t = 0;
    for (int id : ord) {
      const query &tar = qs[id];
      while (t < tar.t) {
        ap(t++, l, r);
      }
      while (tar.t < t) {
        un(--t, l, r);
      }
      while (tar.l < l) {
        al(--l);
      }
      while (r < tar.r) {
        ar(r++);
      }
      while (l < tar.l) {
        dl(l++);
      }
      while (tar.r < r) {
        dr(--r);
      }
      ans(id);
    }
  }
};

} // namespace noya
#ifndef NOYA_MO_WITH_UPDATES_HPP
#define NOYA_MO_WITH_UPDATES_HPP 1

/// @complexity Time: O((N + Q) N^(2/3)) range/time moves with standard blocking.
/// Space: O(N + Q).

#include <algorithm>
#include <cassert>
#include <cmath>
#include <numeric>
#include <tuple>
#include <vector>

namespace noya {

/// @brief Three-dimensional Mo scheduler for offline range queries mixed with
/// point updates; callbacks own the array and aggregate state.
struct mo_with_updates {
  struct query {
    int l = 0;
    int r = 0;
    int t = 0;
  };

  int n = 0;
  int nu = 0;
  std::vector<query> qs;

  mo_with_updates() = default;
  explicit mo_with_updates(int n_) : n(n_) { assert(n >= 0); }

  /// @brief Record one update in chronological order and return its id.
  int add_update() { return nu++; }

  /// @brief Append [l, r) at the current update time and return its id.
  int add_query(int l, int r) {
    assert(0 <= l && l <= r && r <= n);
    int id = int(qs.size());
    qs.push_back({l, r, nu});
    return id;
  }

  /// @brief Process queries while moving a range and time cursor. The update
  /// callbacks receive (update_id, current_left, current_right).
  template <class AddLeft, class AddRight, class RemoveLeft, class RemoveRight,
            class ApplyUpdate, class RollbackUpdate, class Answer>
  void run(AddLeft al, AddRight ar, RemoveLeft dl,
           RemoveRight dr, ApplyUpdate ap,
           RollbackUpdate un, Answer ans) const {
    if (qs.empty()) {
      return;
    }
    int bs = std::max(1, int(std::pow(std::max(1, n), 2.0 / 3.0)));
    std::vector<int> ord(qs.size());
    std::iota(ord.begin(), ord.end(), 0);
    std::sort(ord.begin(), ord.end(), [&](int arr, int B) {
      const query &a = qs[arr];
      const query &b = qs[B];
      int ba = a.l / bs;
      int bb = b.l / bs;
      if (ba != bb) {
        return ba < bb;
      }
      int ra = a.r / bs;
      int rb = b.r / bs;
      if (ra != rb) {
        return (ba & 1) ? ra > rb : ra < rb;
      }
      return ((ba ^ ra) & 1) ? a.t > b.t : a.t < b.t;
    });

    int l = 0;
    int r = 0;
    int t = 0;
    for (int id : ord) {
      const query &tar = qs[id];
      while (t < tar.t) {
        ap(t++, l, r);
      }
      while (tar.t < t) {
        un(--t, l, r);
      }
      while (tar.l < l) {
        al(--l);
      }
      while (r < tar.r) {
        ar(r++);
      }
      while (l < tar.l) {
        dl(l++);
      }
      while (tar.r < r) {
        dr(--r);
      }
      ans(id);
    }
  }
};

} // namespace noya

#endif // NOYA_MO_WITH_UPDATES_HPP
#include <algorithm>
#include <cassert>
#include <cmath>
#include <numeric>
#include <tuple>
#include <vector>

/// @complexity Time: O((N + Q) N^(2/3)) range/time moves with standard blocking.
/// Space: O(N + Q).

namespace noya {

/// @brief Three-dimensional Mo scheduler for offline range queries mixed with
/// point updates; callbacks own the array and aggregate state.
struct mo_with_updates {
  struct query {
    int l = 0;
    int r = 0;
    int t = 0;
  };

  int n = 0;
  int nu = 0;
  std::vector<query> qs;

  mo_with_updates() = default;
  explicit mo_with_updates(int n_) : n(n_) { assert(n >= 0); }

  /// @brief Record one update in chronological order and return its id.
  int add_update() { return nu++; }

  /// @brief Append [l, r) at the current update time and return its id.
  int add_query(int l, int r) {
    assert(0 <= l && l <= r && r <= n);
    int id = int(qs.size());
    qs.push_back({l, r, nu});
    return id;
  }

  /// @brief Process queries while moving a range and time cursor. The update
  /// callbacks receive (update_id, current_left, current_right).
  template <class AddLeft, class AddRight, class RemoveLeft, class RemoveRight,
            class ApplyUpdate, class RollbackUpdate, class Answer>
  void run(AddLeft al, AddRight ar, RemoveLeft dl,
           RemoveRight dr, ApplyUpdate ap,
           RollbackUpdate un, Answer ans) const {
    if (qs.empty()) {
      return;
    }
    int bs = std::max(1, int(std::pow(std::max(1, n), 2.0 / 3.0)));
    std::vector<int> ord(qs.size());
    std::iota(ord.begin(), ord.end(), 0);
    std::sort(ord.begin(), ord.end(), [&](int arr, int B) {
      const query &a = qs[arr];
      const query &b = qs[B];
      int ba = a.l / bs;
      int bb = b.l / bs;
      if (ba != bb) {
        return ba < bb;
      }
      int ra = a.r / bs;
      int rb = b.r / bs;
      if (ra != rb) {
        return (ba & 1) ? ra > rb : ra < rb;
      }
      return ((ba ^ ra) & 1) ? a.t > b.t : a.t < b.t;
    });

    int l = 0;
    int r = 0;
    int t = 0;
    for (int id : ord) {
      const query &tar = qs[id];
      while (t < tar.t) {
        ap(t++, l, r);
      }
      while (tar.t < t) {
        un(--t, l, r);
      }
      while (tar.l < l) {
        al(--l);
      }
      while (r < tar.r) {
        ar(r++);
      }
      while (l < tar.l) {
        dl(l++);
      }
      while (tar.r < r) {
        dr(--r);
      }
      ans(id);
    }
  }
};

} // namespace noya