Submission #262582

#	Time	Username	Problem	Language	Result	Execution time	Memory
262582		KoD	Gap (APIO16_gap)	C++11	30 / 100	68 ms	2196 KiB

gap

/**
 * @title Template
 */

#include "gap.h"
#include <iostream>
#include <algorithm>
#include <utility>
#include <numeric>
#include <vector>
#include <array>
#include <cassert>


template <class T, class U>
bool chmin(T &lhs, const U &rhs) {
  if (lhs > rhs) { 
    lhs = rhs; 
    return true; 
  }
  return false;
}

template <class T, class U>
bool chmax(T &lhs, const U &rhs) {
  if (lhs < rhs) { 
    lhs = rhs; 
    return true; 
  }
  return false;
}

/**
 * @title Chmin/Chmax
 */


class range {
public:
  class iterator {
  private:
    int64_t M_position;

  public:
    iterator(int64_t position) noexcept: M_position(position) { }
    void operator ++ () noexcept { ++M_position; }
    bool operator != (iterator other) const noexcept { return M_position != other.M_position; }
    int64_t operator * () const noexcept { return M_position; }

  };

  class reverse_iterator {
  private:
    int64_t M_position;
  
  public:
    reverse_iterator(int64_t position) noexcept: M_position(position) { }
    void operator ++ () noexcept { --M_position; }
    bool operator != (reverse_iterator other) const noexcept { return M_position != other.M_position; }
    int64_t operator * () const noexcept { return M_position; }

  };
  
private:
  const iterator M_first, M_last;

public:
  range(int64_t first, int64_t last) noexcept: M_first(first), M_last(std::max(first, last)) { }
  iterator begin() const noexcept { return M_first; }
  iterator end() const noexcept { return M_last; }
  reverse_iterator rbegin() const noexcept { return reverse_iterator(*M_last - 1); } 
  reverse_iterator rend() const noexcept { return reverse_iterator(*M_first - 1); } 

};

/**
 * @title Range
 */

#include <type_traits>
#include <iterator>

template <class T>
class rev_impl {
public:
  using iterator = decltype(std::declval<T>().rbegin());

private:
  const iterator M_begin;
  const iterator M_end;

public:
  rev_impl(T &&cont) noexcept: M_begin(cont.rbegin()), M_end(cont.rend()) { }
  iterator begin() const noexcept { return M_begin; }
  iterator end() const noexcept { return M_end; }

};

template <class T>
rev_impl<T> rev(T &&cont) {
  return rev_impl<T>(std::forward<T>(cont));
}

/**
 * @title Reverser
 */

using i32 = int;
using i64 = long long int;
using u32 = unsigned int;
using u64 = unsigned long long int;

constexpr i32 inf32 = (i32(1) << 30) - 1;
constexpr i64 inf64 = (i64(1) << 62) - 1;

#ifdef LOCAL
std::vector<i64> Values;
i64 Queries;
void MinMax(i64 s, i64 t, i64 *mn, i64 *mx) {
  ++Queries;
  assert(s <= t);
  *mn = -1;
  for (auto x: Values) {
    if (x >= s) {
      *mn = x;
      break;
    }
  }
  *mx = -1;
  for (auto x: rev(Values)) {
    if (x <= t) {
      *mx = x;
      break;
    }
  }
}
#endif

i64 findGap(i32 T, i32 N) {
  assert(T == 1);
  std::vector<i64> vec(N + 2);
  i32 l = 0, r = N + 1;
  vec[l] = -1;
  vec[r] = 1000000000000000001;
  while (r - l > 1) {
    i64 mn, mx;
    MinMax(vec[l] + 1, vec[r] - 1, &mn, &mx);
    vec[l + 1] = mn;
    vec[r - 1] = mx;
    ++l;
    --r;
  }
  i64 res = 0;
  for (auto i: range(1, N)) {
    chmax(res, vec[i + 1] - vec[i]);
  }
  return res;
}

#ifdef LOCAL
int main() {
  i32 T, N;
  std::cin >> T >> N;
  Values.resize(N);
  for (auto &x: Values) {
    std::cin >> x;
  }
  std::cout << findGap(T, N) << '\n';
  std::cout << Queries << '\n';
  return 0;
}
#endif

• Subtask 1: 30 / 30
• Subtask 2: 0 / 70