#690764 (C++17(clang)) No.674 n連勤

• 問題: No.674 n連勤
• ユーザー: kkishi
• 提出日時: 2021-08-19 06:14:15
• 言語: C++17(clang) (17.0.6 + boost 1.87.0)
• 結果: AC
• 実行時間: 28 ms / 2,000 ms
• コード長: 9,759 bytes
• コンパイル時間: 5,130 ms
• コンパイル使用メモリ: 165,760 KB
• 実行使用メモリ: 5,248 KB
• 最終ジャッジ日時: 2024-10-12 03:33:32
• 合計ジャッジ時間: 4,633 ms
• ジャッジサーバーID （参考情報）: judge1 / judge4

ファイルパターン	結果
sample	AC * 3
other	AC * 17

ソースコード

#include <bits/stdc++.h>

// Interval represents [left, right) with value.
struct Interval {
  int64_t left, right, value;
  bool Contains(int64_t x) const { return left <= x && x < right; }
  bool operator<(const Interval& i) const { return left < i.left; };
};

std::ostream& operator<<(std::ostream& os, const Interval& i) {
  os << "[" << i.left << "," << i.right << ")";
  if (i.value != 0) os << "=" << i.value;
  return os;
}

class Intervals : public std::set<Interval> {
 public:
  // Inserts an interval [left, right) with vlaue. If it would result in
  // consecutive intervals with the same value, they are concatenated.
  //
  // NOTE: The new interval must not overlap with any existing intervals. Call
  // Erase first to ensure that if necessary.
  void Insert(int64_t left, int64_t right, int64_t value = 0) {
    auto it = LowerBound(left);
    if (it != begin()) {
      auto pit = prev(it);
      assert(pit->right <= left);  // Assert no overlap on the left.
      if (pit->right == left && pit->value == value) {
        left = pit->left;
        erase(pit);
      }
    }
    if (it != end()) {
      assert(right <= it->left);  // Assert no overlap on the right.
      if (right == it->left && value == it->value) {
        right = it->right;
        erase(it);
      }
    }
    insert({left, right, value});
  }

  // Erases intervals that overlap with [left, right). Partial overlaps are
  // erased partially. Returns erased intervals.
  std::vector<Interval> Erase(int64_t left, int64_t right) {
    auto it = LowerBound(left), jt = it;
    while (jt != end() && jt->left < right) ++jt;
    std::vector<Interval> erased(it, jt);
    erase(it, jt);
    if (!erased.empty()) {
      if (auto& i = erased[0]; i.left < left) {
        insert({i.left, left, i.value});
        i.left = left;
      }
      if (auto& i = erased.back(); right < i.right) {
        insert({right, i.right, i.value});
        i.right = right;
      }
    }
    return erased;
  }

  // Returns the first interval that either contains x or is on the right of x.
  std::set<Interval>::iterator LowerBound(int64_t x) const {
    auto it = lower_bound({x, 0, 0});
    if (it != begin() && x < prev(it)->right) --it;
    return it;
  }

  // Returns an interval containing x if exists.
  std::optional<Interval> Find(int64_t x) const {
    auto it = LowerBound(x);
    if (it != end() && it->Contains(x)) return *it;
    return std::nullopt;
  }

  // Returns mex[left, infinity).
  int64_t Mex(int64_t left) const {
    auto i = Find(left);
    return i ? i->right : left;
  }
};
#include <boost/hana/functional/fix.hpp>

template <typename T, typename = void>
struct is_dereferenceable : std::false_type {};
template <typename T>
struct is_dereferenceable<T, std::void_t<decltype(*std::declval<T>())>>
    : std::true_type {};

template <typename T, typename = void>
struct is_iterable : std::false_type {};
template <typename T>
struct is_iterable<T, std::void_t<decltype(std::begin(std::declval<T>())),
                                  decltype(std::end(std::declval<T>()))>>
    : std::true_type {};

template <typename T, typename = void>
struct is_applicable : std::false_type {};
template <typename T>
struct is_applicable<T, std::void_t<decltype(std::tuple_size<T>::value)>>
    : std::true_type {};

template <typename T, typename... Ts>
void debug(const T& value, const Ts&... args);
template <typename T>
void debug(const T& v) {
  if constexpr (is_dereferenceable<T>::value) {
    std::cerr << "{";
    if (v) {
      debug(*v);
    } else {
      std::cerr << "nil";
    }
    std::cerr << "}";
  } else if constexpr (is_iterable<T>::value &&
                       !std::is_same<T, std::string>::value) {
    std::cerr << "{";
    for (auto it = std::begin(v); it != std::end(v); ++it) {
      if (it != std::begin(v)) std::cerr << ", ";
      debug(*it);
    }
    std::cerr << "}";
  } else if constexpr (is_applicable<T>::value) {
    std::cerr << "{";
    std::apply([](const auto&... args) { debug(args...); }, v);
    std::cerr << "}";
  } else {
    std::cerr << v;
  }
}
template <typename T, typename... Ts>
void debug(const T& value, const Ts&... args) {
  debug(value);
  std::cerr << ", ";
  debug(args...);
}
#if DEBUG
#define dbg(...)                        \
  do {                                  \
    cerr << #__VA_ARGS__ << ": ";       \
    debug(__VA_ARGS__);                 \
    cerr << " (L" << __LINE__ << ")\n"; \
  } while (0)
#else
#define dbg(...)
#endif

void read_from_cin() {}
template <typename T, typename... Ts>
void read_from_cin(T& value, Ts&... args) {
  std::cin >> value;
  read_from_cin(args...);
}
#define rd(type, ...) \
  type __VA_ARGS__;   \
  read_from_cin(__VA_ARGS__);
#define ints(...) rd(int, __VA_ARGS__);
#define strings(...) rd(string, __VA_ARGS__);

// Strings used for yes/no questions. Defined as variables so that it can be
// adjusted for each contest site.
const char *yes_str = "Yes", *no_str = "No";

template <typename T>
void write_to_cout(const T& value) {
  if constexpr (std::is_same<T, bool>::value) {
    std::cout << (value ? yes_str : no_str);
  } else if constexpr (is_iterable<T>::value &&
                       !std::is_same<T, std::string>::value) {
    for (auto it = std::begin(value); it != std::end(value); ++it) {
      if (it != std::begin(value)) std::cout << " ";
      std::cout << *it;
    }
  } else {
    std::cout << value;
  }
}
template <typename T, typename... Ts>
void write_to_cout(const T& value, const Ts&... args) {
  write_to_cout(value);
  std::cout << ' ';
  write_to_cout(args...);
}
#define wt(...)                 \
  do {                          \
    write_to_cout(__VA_ARGS__); \
    cout << '\n';               \
  } while (0)

#define all(x) (x).begin(), (x).end()
#define eb(...) emplace_back(__VA_ARGS__)
#define pb(...) push_back(__VA_ARGS__)

#define dispatch(_1, _2, _3, name, ...) name

#define as_i64(x)                                                          \
  (                                                                        \
      [] {                                                                 \
        static_assert(                                                     \
            std::is_integral<                                              \
                typename std::remove_reference<decltype(x)>::type>::value, \
            "rep macro supports std integral types only");                 \
      },                                                                   \
      static_cast<int64_t>(x))

#define rep3(i, a, b) for (int64_t i = as_i64(a); i < as_i64(b); ++i)
#define rep2(i, n) rep3(i, 0, n)
#define rep1(n) rep2(_loop_variable_, n)
#define rep(...) dispatch(__VA_ARGS__, rep3, rep2, rep1)(__VA_ARGS__)

#define rrep3(i, a, b) for (int64_t i = as_i64(b) - 1; i >= as_i64(a); --i)
#define rrep2(i, n) rrep3(i, 0, n)
#define rrep1(n) rrep2(_loop_variable_, n)
#define rrep(...) dispatch(__VA_ARGS__, rrep3, rrep2, rrep1)(__VA_ARGS__)

#define each3(k, v, c) for (auto&& [k, v] : c)
#define each2(e, c) for (auto&& e : c)
#define each(...) dispatch(__VA_ARGS__, each3, each2)(__VA_ARGS__)

template <typename T>
std::istream& operator>>(std::istream& is, std::vector<T>& v) {
  for (T& vi : v) is >> vi;
  return is;
}

template <typename T, typename U>
std::istream& operator>>(std::istream& is, std::pair<T, U>& p) {
  is >> p.first >> p.second;
  return is;
}

template <typename T, typename U>
bool chmax(T& a, U b) {
  if (a < b) {
    a = b;
    return true;
  }
  return false;
}

template <typename T, typename U>
bool chmin(T& a, U b) {
  if (a > b) {
    a = b;
    return true;
  }
  return false;
}

template <typename T, typename U>
auto max(T a, U b) {
  return a > b ? a : b;
}

template <typename T, typename U>
auto min(T a, U b) {
  return a < b ? a : b;
}

template <typename T>
int64_t sz(const T& v) {
  return std::size(v);
}

template <typename T>
int64_t popcount(T i) {
  return std::bitset<std::numeric_limits<T>::digits>(i).count();
}

template <typename T>
bool hasbit(T s, int i) {
  return std::bitset<std::numeric_limits<T>::digits>(s)[i];
}

template <typename T, typename U>
auto div_floor(T n, U d) {
  if (d < 0) {
    n = -n;
    d = -d;
  }
  if (n < 0) {
    return -((-n + d - 1) / d);
  }
  return n / d;
};

template <typename T, typename U>
auto div_ceil(T n, U d) {
  if (d < 0) {
    n = -n;
    d = -d;
  }
  if (n < 0) {
    return -(-n / d);
  }
  return (n + d - 1) / d;
}

template <typename T>
bool even(T x) {
  return x % 2 == 0;
}

std::array<std::pair<int64_t, int64_t>, 4> adjacent(int64_t i, int64_t j) {
  return {{{i + 1, j}, {i, j + 1}, {i - 1, j}, {i, j - 1}}};
}

bool inside(int64_t i, int64_t j, int64_t I, int64_t J) {
  return 0 <= i && i < I && 0 <= j && j < J;
}

constexpr int64_t int_pow(int64_t b, int64_t e) {
  int64_t x = 1;
  for (int64_t i = 0; i < e; ++i) {
    x *= b;
  }
  return x;
}

// big = 2305843009213693951 = 2^61-1 ~= 2.3*10^18
const int64_t big = std::numeric_limits<int64_t>::max() / 4;

using i64 = int64_t;
using i32 = int32_t;

template <typename T>
using low_priority_queue =
    std::priority_queue<T, std::vector<T>, std::greater<T>>;

template <typename T>
using V = std::vector<T>;
template <typename T>
using VV = V<V<T>>;

void Main();

int main() {
  std::ios_base::sync_with_stdio(false);
  std::cin.tie(NULL);
  std::cout << std::fixed << std::setprecision(20);
  Main();
  return 0;
}

const auto& Fix = boost::hana::fix;

using namespace std;

#define int i64

void Main() {
  ints(d, q);
  Intervals is;
  int ans = -big;
  rep(q) {
    ints(a, b);
    --a;
    is.Erase(a, b);
    is.Insert(a, b);
    auto i = is.Find(a);
    chmax(ans, i->right - i->left);
    wt(ans);
  }
}