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

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define P pair<ll, ll>
#define FOR(I, A, B) for (ll I = ll(A); I < ll(B); ++I)
#define FORR(I, A, B) for (ll I = ll((B)-1); I >= ll(A); --I)
#define TO(x, t, f) ((x) ? (t) : (f))
#define SORT(x) (sort(x.begin(), x.end())) // 0 2 2 3 4 5 8 9
#define POSL(x, v)                                                             \\
  (lower_bound(x.begin(), x.end(), v) - x.begin()) // xi>=v  x is sorted
#define POSU(x, v)                                                             \\
  (upper_bound(x.begin(), x.end(), v) - x.begin()) // xi>v  x is sorted
#define NUM(x, v) (POSU(x, v) - POSL(x, v))        // x is sorted
#define REV(x) (reverse(x.begin(), x.end()))       // reverse
ll gcd_(ll a, ll b) {
  if (a % b == 0)
    return b;
  return gcd_(b, a % b);
}
ll lcm_(ll a, ll b) {
  ll c = gcd_(a, b);
  return ((a / c) * (b / c) * c);
}
#define NEXTP(x) next_permutation(x.begin(), x.end())
const ll INF = ll(1e16) + ll(7);
const ll MOD = 1000000007LL;
#define out(a) cout << fixed << setprecision((a))
// tie(a,b,c) = make_tuple(10,9,87);
#define pop_(a) __builtin_popcount((a))
ll keta(ll a) {
  ll r = 0;
  while (a) {
    a /= 10;
    r++;
  }
  return r;
}

int main() {

  ll N, K;
  cin >> N >> K;
  vector<ll> a(N);
  FOR(i, 0, N) { cin >> a[i]; }
  ll ng = 0, ok = MOD; //
  while (ok - ng > 1) {
    ll mid = (ok + ng) / 2;
    ll cnt = 0;
    FOR(i, 0, N) {
      cnt += a[i] / mid;
      if (a[i] % mid == 0)
        cnt--;
    }
    if (cnt <= K) {
      ok = mid;
    } else {
      ng = mid;
    }
  }
  cout << ok << endl;
}


Error: TLE

Fixed submission:

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define P pair<ll, ll>
#define FOR(I, A, B) for (ll I = ll(A); I < ll(B); ++I)
#define FORR(I, A, B) for (ll I = ll((B)-1); I >= ll(A); --I)
#define TO(x, t, f) ((x) ? (t) : (f))
#define SORT(x) (sort(x.begin(), x.end())) // 0 2 2 3 4 5 8 9
#define POSL(x, v)                                                             \\
  (lower_bound(x.begin(), x.end(), v) - x.begin()) // xi>=v  x is sorted
#define POSU(x, v)                                                             \\
  (upper_bound(x.begin(), x.end(), v) - x.begin()) // xi>v  x is sorted
#define NUM(x, v) (POSU(x, v) - POSL(x, v))        // x is sorted
#define REV(x) (reverse(x.begin(), x.end()))       // reverse
ll gcd_(ll a, ll b) {
  if (a % b == 0)
    return b;
  return gcd_(b, a % b);
}
ll lcm_(ll a, ll b) {
  ll c = gcd_(a, b);
  return ((a / c) * (b / c) * c);
}
#define NEXTP(x) next_permutation(x.begin(), x.end())
const ll INF = ll(1e16) + ll(7);
const ll MOD = 1000000007LL;
#define out(a) cout << fixed << setprecision((a))
// tie(a,b,c) = make_tuple(10,9,87);
#define pop_(a) __builtin_popcount((a))
ll keta(ll a) {
  ll r = 0;
  while (a) {
    a /= 10;
    r++;
  }
  return r;
}

int main() {

  ll N, K;
  cin >> N >> K;
  priority_queue<ll> a;
  FOR(i, 0, N) {
    ll v;
    cin >> v;
    a.push(v);
  }
  ll ng = 0, ok = MOD; //

  while (ok - ng > 1) {
    ll mid = (ok + ng) / 2;
    priority_queue<ll> b;
    b = a;
    FOR(i, 0, K) {
      if (b.top() <= mid)
        break;
      ll len = b.top();
      b.pop();
      b.push(len - mid);
      b.push(mid);
    }
    if (b.top() <= mid) {
      ok = mid;
    } else {
      ng = mid;
    }
  }
  cout << ok << endl;
}