Problem p02598 (C++) — buggy submission, verdict: Time Limit Exceeded

// atcoder/abc174/E/main.cpp
// author: @___Johniel
// github: https://github.com/johniel/

#include <bits/stdc++.h>

#define each(i, c) for (auto &i : c)
#define unless(cond) if (!(cond))

using namespace std;

template <typename P, typename Q>
ostream &operator<<(ostream &os, pair<P, Q> p) {
  os << "(" << p.first << "," << p.second << ")";
  return os;
}
template <typename P, typename Q>
istream &operator>>(istream &is, pair<P, Q> &p) {
  is >> p.first >> p.second;
  return is;
}
template <typename T> ostream &operator<<(ostream &os, vector<T> v) {
  os << "(";
  for (auto &i : v)
    os << i << ",";
  os << ")";
  return os;
}
template <typename T> istream &operator>>(istream &is, vector<T> &v) {
  for (auto &i : v)
    is >> i;
  return is;
}
template <typename T> ostream &operator<<(ostream &os, set<T> s) {
  os << "#{";
  for (auto &i : s)
    os << i << ",";
  os << "}";
  return os;
}
template <typename K, typename V>
ostream &operator<<(ostream &os, map<K, V> m) {
  os << "{";
  for (auto &i : m)
    os << i << ",";
  os << "}";
  return os;
}

template <typename T> inline T setmax(T &a, T b) { return a = std::max(a, b); }
template <typename T> inline T setmin(T &a, T b) { return a = std::min(a, b); }

using lli = long long int;
using ull = unsigned long long;
using point = complex<double>;
using str = string;
template <typename T> using vec = vector<T>;

constexpr array<int, 8> di({0, 1, -1, 0, 1, -1, 1, -1});
constexpr array<int, 8> dj({1, 0, 0, -1, 1, -1, -1, 1});
constexpr lli mod = 1e9 + 7;

int main(int argc, char *argv[]) {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.setf(ios_base::fixed);
  cout.precision(15);

  int n, k;
  while (cin >> n >> k) {
    vec<lli> a(n);
    cin >> a;

    auto fn = [&](lli x) {
      lli y = 0;
      each(i, a) {
        if (i % x)
          y += i / x;
        else
          y += max<lli>(0LL, (i / x) - 1);
      }
      return y <= k;
    };

    lli small = 0;
    lli large = 1LL << 60;
    while (small + 1 < large) {
      lli mid = (small + large) / 2;
      if (fn(mid))
        large = mid;
      else
        small = mid;
    }
    cout << large << endl;
  }

  return 0;
}


Error: TLE

Fixed submission:

// atcoder/abc174/E/main.cpp
// author: @___Johniel
// github: https://github.com/johniel/

#include <bits/stdc++.h>

#define each(i, c) for (auto &i : c)
#define unless(cond) if (!(cond))

using namespace std;

template <typename P, typename Q>
ostream &operator<<(ostream &os, pair<P, Q> p) {
  os << "(" << p.first << "," << p.second << ")";
  return os;
}
template <typename P, typename Q>
istream &operator>>(istream &is, pair<P, Q> &p) {
  is >> p.first >> p.second;
  return is;
}
template <typename T> ostream &operator<<(ostream &os, vector<T> v) {
  os << "(";
  for (auto &i : v)
    os << i << ",";
  os << ")";
  return os;
}
template <typename T> istream &operator>>(istream &is, vector<T> &v) {
  for (auto &i : v)
    is >> i;
  return is;
}
template <typename T> ostream &operator<<(ostream &os, set<T> s) {
  os << "#{";
  for (auto &i : s)
    os << i << ",";
  os << "}";
  return os;
}
template <typename K, typename V>
ostream &operator<<(ostream &os, map<K, V> m) {
  os << "{";
  for (auto &i : m)
    os << i << ",";
  os << "}";
  return os;
}

template <typename T> inline T setmax(T &a, T b) { return a = std::max(a, b); }
template <typename T> inline T setmin(T &a, T b) { return a = std::min(a, b); }

using lli = long long int;
using ull = unsigned long long;
using point = complex<double>;
using str = string;
template <typename T> using vec = vector<T>;

constexpr array<int, 8> di({0, 1, -1, 0, 1, -1, 1, -1});
constexpr array<int, 8> dj({1, 0, 0, -1, 1, -1, -1, 1});
constexpr lli mod = 1e9 + 7;

int main(int argc, char *argv[]) {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.setf(ios_base::fixed);
  cout.precision(15);

  int n, k;
  while (cin >> n >> k) {
    vec<double> a(n);
    cin >> a;

    auto fn = [&](lli x) {
      priority_queue<lli> q;
      each(i, a) q.push(i);
      for (int _ = 0; _ < k && q.size(); ++_) {
        lli y = q.top();
        q.pop();
        if (x < y) {
          q.push(y - x);
        }
      }
      return q.empty() || (q.top() <= x);
    };

    lli small = 0;
    lli large = 1LL << 60;
    while (small + 1 < large) {
      lli mid = (small + large) / 2;
      if (fn(mid))
        large = mid;
      else
        small = mid;
    }
    cout << large << endl;
  }

  return 0;
}