Problem p02598 (C++) — buggy submission, verdict: Runtime Error

#include "bits/stdc++.h"
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
const int INF = 1e9;
const ll LINF = 1e18;
inline ll gcd(ll a, ll b) { return b ? gcd(b, a % b) : a; }
inline ll lcm(ll a, ll b) { return a / gcd(a, b) * b; }
template <class S, class T>
ostream &operator<<(ostream &out, const pair<S, T> &o) {
  out << "(" << o.first << "," << o.second << ")";
  return out;
}
template <class T> ostream &operator<<(ostream &out, const vector<T> &V) {
  for (int i = 0; i < V.size(); i++) {
    out << V[i];
    if (i != V.size() - 1)
      out << " ";
  }
  return out;
}
template <class T>
ostream &operator<<(ostream &out, const vector<vector<T>> &Mat) {
  for (int i = 0; i < Mat.size(); i++) {
    if (i != 0)
      out << endl;
    out << Mat[i];
  }
  return out;
}
template <class S, class T>
ostream &operator<<(ostream &out, const map<S, T> &mp) {
  out << "{ ";
  for (auto it = mp.begin(); it != mp.end(); it++) {
    out << it->first << ":" << it->second;
    if (mp.size() - 1 != distance(mp.begin(), it))
      out << ", ";
  }
  out << " }";
  return out;
}
template <typename T> vector<T> make_v(size_t a) { return vector<T>(a); }
template <typename T, typename... Ts> auto make_v(size_t a, Ts... ts) {
  return vector<decltype(make_v<T>(ts...))>(a, make_v<T>(ts...));
}
template <typename T, typename V>
typename enable_if<is_class<T>::value == 0>::type fill_v(T &t, const V &v) {
  t = v;
}
template <typename T, typename V>
typename enable_if<is_class<T>::value != 0>::type fill_v(T &t, const V &v) {
  for (auto &e : t)
    fill_v(e, v);
}
/*
 <url:>
 問題文============================================================
 =================================================================
 解説=============================================================
 ================================================================
 */

template <class Type> Type solve(Type res = Type()) {
  ll N, K;
  cin >> N >> K;
  vector<ll> A(N);
  for (auto &in : A)
    cin >> in;

  sort(A.begin(), A.end());

  if (K == 0)
    return A.back();

  auto ok = [&](double m) {
    ll cnt = 0;
    for (int i = 0; i < N; i++) {
      cnt += ceil(A[i] / m) - 1;
      if (cnt > K)
        return false;
    }
    return true;
  };
  double l = 0.5, r = 2 * INF;
  for (int i = 0; i < 300; i++) {

    double m = (l + r) / 2;

    if (ok(m))
      r = m;
    else
      l = m;
  }
  res = ceil(r);
  return res;
}
int main(void) {
  cin.tie(0);
  ios_base::sync_with_stdio(false);
  // solve(0);
  cout << fixed << setprecision(15) << solve<ll>() << endl;
  return 0;
}


Error: 0

Fixed submission:

#include "bits/stdc++.h"
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
const int INF = 1e9;
const ll LINF = 1e18;
inline ll gcd(ll a, ll b) { return b ? gcd(b, a % b) : a; }
inline ll lcm(ll a, ll b) { return a / gcd(a, b) * b; }
template <class S, class T>
ostream &operator<<(ostream &out, const pair<S, T> &o) {
  out << "(" << o.first << "," << o.second << ")";
  return out;
}
template <class T> ostream &operator<<(ostream &out, const vector<T> &V) {
  for (int i = 0; i < V.size(); i++) {
    out << V[i];
    if (i != V.size() - 1)
      out << " ";
  }
  return out;
}
template <class T>
ostream &operator<<(ostream &out, const vector<vector<T>> &Mat) {
  for (int i = 0; i < Mat.size(); i++) {
    if (i != 0)
      out << endl;
    out << Mat[i];
  }
  return out;
}
template <class S, class T>
ostream &operator<<(ostream &out, const map<S, T> &mp) {
  out << "{ ";
  for (auto it = mp.begin(); it != mp.end(); it++) {
    out << it->first << ":" << it->second;
    if (mp.size() - 1 != distance(mp.begin(), it))
      out << ", ";
  }
  out << " }";
  return out;
}
template <typename T> vector<T> make_v(size_t a) { return vector<T>(a); }
template <typename T, typename... Ts> auto make_v(size_t a, Ts... ts) {
  return vector<decltype(make_v<T>(ts...))>(a, make_v<T>(ts...));
}
template <typename T, typename V>
typename enable_if<is_class<T>::value == 0>::type fill_v(T &t, const V &v) {
  t = v;
}
template <typename T, typename V>
typename enable_if<is_class<T>::value != 0>::type fill_v(T &t, const V &v) {
  for (auto &e : t)
    fill_v(e, v);
}
/*
 <url:>
 問題文============================================================
 =================================================================
 解説=============================================================
 ================================================================
 */

template <class Type> Type solve(Type res = Type()) {
  ll N, K;
  cin >> N >> K;
  vector<ll> A(N);
  for (auto &in : A)
    cin >> in;

  sort(A.begin(), A.end());

  if (K == 0)
    return A.back();

  //    auto ok = [&](double m){
  //
  //        ll cnt = 0;
  //        for(int i = 0; i < N;i++){
  //            cnt += floor(A[i]/m);
  //            if(cnt > K) return false;
  //        }
  //        return true;
  //    };
  //    double l = 0.5, r = 2*INF;
  //    for(int i = 0; i < 300; i++){
  //
  //        double m = (l+r)/2;
  //
  //        if(ok(m)) r = m;
  //        else l = m;
  //    }
  // cout << l << " " << r << endl;
  // cout << l << " " << r << endl;
  // res = ceil(r);

  auto ok = [&](ll m) {
    ll cnt = 0;
    for (int i = 0; i < N; i++) {
      cnt += A[i] / m;
      if (cnt > K)
        return false;
    }
    return true;
  };
  ll l = 0, r = 2 * INF;
  for (int i = 0; i < 300; i++) {

    ll m = (l + r) / 2;

    if (ok(m))
      r = m;
    else
      l = m;
  }
  // cout << l << " " << r << endl;
  res = r;
  return res;
}
int main(void) {
  cin.tie(0);
  ios_base::sync_with_stdio(false);
  // solve(0);
  cout << fixed << setprecision(15) << solve<ll>() << endl;
  return 0;
}