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

/*
ID: varunra2
LANG: C++
TASK: a
*/

#include <bits/stdc++.h>
using namespace std;

#ifdef DEBUG
#include "lib/debug.h"
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
#pragma GCC diagnostic ignored "-Wsign-compare"
// #pragma GCC diagnostic ignored "-Wunused-parameter"
// #pragma GCC diagnostic ignored "-Wunused-variable"
#else
#define debug(...) 42
#endif

#define EPS 1e-9
#define IN(A, B, C) assert(B <= A && A <= C)
#define INF (int)1e9
#define MEM(a, b) memset(a, (b), sizeof(a))
#define MOD 1000000007
#define MP make_pair
#define PB push_back
#define all(cont) cont.begin(), cont.end()
#define rall(cont) cont.end(), cont.begin()
#define x first
#define y second

const double PI = acos(-1.0);
typedef long long ll;
typedef long double ld;
typedef pair<int, int> PII;
typedef map<int, int> MPII;
typedef multiset<int> MSETI;
typedef set<int> SETI;
typedef set<string> SETS;
typedef vector<int> VI;
typedef vector<PII> VII;
typedef vector<VI> VVI;
typedef vector<string> VS;

#define rep(i, a, b) for (int i = a; i < (b); ++i)
#define trav(a, x) for (auto &a : x)
#define sz(x) (int)(x).size()
typedef pair<int, int> pii;
typedef vector<int> vi;
#pragma GCC diagnostic ignored "-Wsign-compare"
// util functions

int n, k;
VI vals;

void init() {
  cin >> n >> k;
  vals.resize(n);
  for (int i = 0; i < n; i++) {
    cin >> vals[i];
  }
}

bool ok(int len) {
  if (len == 0)
    return false;
  int cop = k;
  for (int i = 0; i < n; i++) {
    // chop up vals[i] into vals[i]/len parts
    int cur = vals[i] / len + (bool)(vals[i] % len) - 1;
    cop -= cur;
  }
  return cop >= 0;
}

int main() {
  cin.sync_with_stdio(0);
  cin.tie(0);

  init();
  int mx = 0;
  for (auto &x : vals)
    mx = max(mx, x);
  int x = -1;
  for (int b = mx + 10; b >= 1; b /= 2) {
    while (!ok(x + b))
      x += b;
  }
  k = x + 1;

  cout << k << endl;

  return 0;
}


Error: 0

Fixed submission:

/*
ID: varunra2
LANG: C++
TASK: a
*/

#include <bits/stdc++.h>
using namespace std;

#ifdef DEBUG
#include "lib/debug.h"
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
#pragma GCC diagnostic ignored "-Wsign-compare"
// #pragma GCC diagnostic ignored "-Wunused-parameter"
// #pragma GCC diagnostic ignored "-Wunused-variable"
#else
#define debug(...) 42
#endif

#define EPS 1e-9
#define IN(A, B, C) assert(B <= A && A <= C)
#define INF (int)1e9
#define MEM(a, b) memset(a, (b), sizeof(a))
#define MOD 1000000007
#define MP make_pair
#define PB push_back
#define all(cont) cont.begin(), cont.end()
#define rall(cont) cont.end(), cont.begin()
#define x first
#define y second

const double PI = acos(-1.0);
typedef long long ll;
typedef long double ld;
typedef pair<int, int> PII;
typedef map<int, int> MPII;
typedef multiset<int> MSETI;
typedef set<int> SETI;
typedef set<string> SETS;
typedef vector<int> VI;
typedef vector<PII> VII;
typedef vector<VI> VVI;
typedef vector<string> VS;

#define rep(i, a, b) for (int i = a; i < (b); ++i)
#define trav(a, x) for (auto &a : x)
#define sz(x) (int)(x).size()
typedef pair<int, int> pii;
typedef vector<int> vi;
#pragma GCC diagnostic ignored "-Wsign-compare"
// util functions

int n, k;
VI vals;

void init() {
  cin >> n >> k;
  vals.resize(n);
  for (int i = 0; i < n; i++) {
    cin >> vals[i];
  }
}

bool ok(int len) {
  int cop = k;
  for (int i = 0; i < n; i++) {
    // chop up vals[i] into vals[i]/len parts
    int cur = vals[i] / len + (bool)(vals[i] % len) - 1;
    cop -= cur;
  }
  return cop >= 0;
}

int main() {
  cin.sync_with_stdio(0);
  cin.tie(0);

  init();

  int x = -1;
  for (int b = *max_element(all(vals)) + 10; b >= 1; b /= 2) {
    while (!ok(x + b))
      x += b;
  }
  k = x + 1;

  cout << k << endl;

  return 0;
}