Problem p00487 (C++) — buggy submission, verdict: Runtime Error

#include <algorithm>
#include <cassert>
#include <cfloat>
#include <climits>
#include <cmath>
#include <complex>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <functional>
#include <iomanip>
#include <iostream>
#include <list>
#include <map>
#include <memory>
#include <numeric>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <utility>
#include <vector>

using namespace std;

#if __GNUC__
#include <tr1/unordered_map>
#include <tr1/unordered_set>
using namespace tr1;
#else
#include <unordered_map>
#include <unordered_set>
#endif

#ifdef _MSC_VER
#define __typeof__ decltype
template <class T> int popcount(T n) {
  return n ? 1 + popcount(n & (n - 1)) : 0;
}
#endif
#ifdef __GNUC__
template <class T> int popcount(T n);
template <> int popcount(unsigned int n) { return __builtin_popcount(n); }
template <> int popcount(int n) { return __builtin_popcount(n); }
template <> int popcount(unsigned long long n) {
  return __builtin_popcountll(n);
}
template <> int popcount(long long n) { return __builtin_popcountll(n); }
#endif

#define rep(i, n) for (int i = 0; i < (int)n; ++i)
#define foreach(it, c)                                                         \\
  for (__typeof__((c).begin()) it = (c).begin(); it != (c).end(); ++it)
#define rforeach(it, c)                                                        \\
  for (__typeof__((c).rbegin()) it = (c).rbegin(); it != (c).rend(); ++it)
#define all(c) (c).begin(), (c).end()
#define rall(c) (c).rbegin(), (c).rend()
#define CL(arr, val) memset(arr, val, sizeof(arr))
#define COPY(dest, src) memcpy(dest, src, sizeof(src))

template <class T> void max_swap(T &a, const T &b) { a = max(a, b); }
template <class T> void min_swap(T &a, const T &b) { a = min(a, b); }

typedef long long ll;
typedef pair<int, int> pint;

template <class T> string to_s(const T &a) {
  ostringstream os;
  os << a;
  return os.str();
}

const double EPS = 1e-8;
const double PI = acos(-1.0);
const int dx[] = {0, 1, 0, -1};
const int dy[] = {1, 0, -1, 0};
bool valid_pos(int x, int y, int w, int h) {
  return 0 <= x && x < w && 0 <= y && y < h;
}

template <class T>
void print(T a, int n, int br = 1, const string &deli = ", ") {
  cout << "{ ";
  for (int i = 0; i < n; ++i) {
    cout << a[i];
    if (i + 1 != n)
      cout << deli;
  }
  cout << " }";
  while (br--)
    cout << endl;
}
template <class T>
void print(const vector<T> &v, int br = 1, const string &deli = ", ") {
  print(v, v.size(), br, deli);
}
template <class T> void print2d(T a, int w, int h, int width = -1, int br = 1) {
  for (int i = 0; i < h; ++i) {
    for (int j = 0; j < w; ++j) {
      if (width != -1)
        cout.width(width);
      cout << a[i][j] << ' ';
    }
    cout << endl;
  }
  while (br--)
    cout << endl;
}

template <class T> void input(int n, T &a) {
  for (int i = 0; i < n; ++i)
    cin >> a[i];
}
template <class T, class U> void input(int n, T &a, U &b) {
  for (int i = 0; i < n; ++i)
    cin >> a[i] >> b[i];
}

int n;
pair<int, int> t[3 * 114514];
bool ok(ll k) {
  ll sum = 0;
  priority_queue<int> q;
  for (int i = 0; i < k - 1; ++i) {
    sum += t[i].second;
    q.push(t[i].second);
  }

  const int dummy = 1 << 26;
  sum += dummy;
  q.push(dummy);

  for (int i = k - 1; i < n; ++i) {
    int a = t[i].second, b = t[i].first;

    if (a < q.top()) {
      sum -= q.top();
      q.pop();
      sum += a;
      q.push(a);

      if (sum <= b * k)
        return true;
    }
  }

  return false;
}
int main() {
  ios::sync_with_stdio(false);

  cin >> n;
  for (int i = 0; i < n; ++i)
    cin >> t[i].second >> t[i].first;
  sort(t, t + n, greater<pint>());

  int low = 0, high = n + 1;
  while (low + 1 < high) {
    int mid = (low + high) / 2;
    if (ok(mid))
      low = mid;
    else
      high = mid;
  }

  cout << low << endl;
}

Error: 0

Fixed submission:

#include <algorithm>
#include <cassert>
#include <cfloat>
#include <climits>
#include <cmath>
#include <complex>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <functional>
#include <iomanip>
#include <iostream>
#include <list>
#include <map>
#include <memory>
#include <numeric>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <utility>
#include <vector>

using namespace std;

#if __GNUC__
#include <tr1/unordered_map>
#include <tr1/unordered_set>
using namespace tr1;
#else
#include <unordered_map>
#include <unordered_set>
#endif

#ifdef _MSC_VER
#define __typeof__ decltype
template <class T> int popcount(T n) {
  return n ? 1 + popcount(n & (n - 1)) : 0;
}
#endif
#ifdef __GNUC__
template <class T> int popcount(T n);
template <> int popcount(unsigned int n) { return __builtin_popcount(n); }
template <> int popcount(int n) { return __builtin_popcount(n); }
template <> int popcount(unsigned long long n) {
  return __builtin_popcountll(n);
}
template <> int popcount(long long n) { return __builtin_popcountll(n); }
#endif

#define rep(i, n) for (int i = 0; i < (int)n; ++i)
#define foreach(it, c)                                                         \\
  for (__typeof__((c).begin()) it = (c).begin(); it != (c).end(); ++it)
#define rforeach(it, c)                                                        \\
  for (__typeof__((c).rbegin()) it = (c).rbegin(); it != (c).rend(); ++it)
#define all(c) (c).begin(), (c).end()
#define rall(c) (c).rbegin(), (c).rend()
#define CL(arr, val) memset(arr, val, sizeof(arr))
#define COPY(dest, src) memcpy(dest, src, sizeof(src))

template <class T> void max_swap(T &a, const T &b) { a = max(a, b); }
template <class T> void min_swap(T &a, const T &b) { a = min(a, b); }

typedef long long ll;
typedef pair<int, int> pint;

template <class T> string to_s(const T &a) {
  ostringstream os;
  os << a;
  return os.str();
}

const double EPS = 1e-8;
const double PI = acos(-1.0);
const int dx[] = {0, 1, 0, -1};
const int dy[] = {1, 0, -1, 0};
bool valid_pos(int x, int y, int w, int h) {
  return 0 <= x && x < w && 0 <= y && y < h;
}

template <class T>
void print(T a, int n, int br = 1, const string &deli = ", ") {
  cout << "{ ";
  for (int i = 0; i < n; ++i) {
    cout << a[i];
    if (i + 1 != n)
      cout << deli;
  }
  cout << " }";
  while (br--)
    cout << endl;
}
template <class T>
void print(const vector<T> &v, int br = 1, const string &deli = ", ") {
  print(v, v.size(), br, deli);
}
template <class T> void print2d(T a, int w, int h, int width = -1, int br = 1) {
  for (int i = 0; i < h; ++i) {
    for (int j = 0; j < w; ++j) {
      if (width != -1)
        cout.width(width);
      cout << a[i][j] << ' ';
    }
    cout << endl;
  }
  while (br--)
    cout << endl;
}

template <class T> void input(int n, T &a) {
  for (int i = 0; i < n; ++i)
    cin >> a[i];
}
template <class T, class U> void input(int n, T &a, U &b) {
  for (int i = 0; i < n; ++i)
    cin >> a[i] >> b[i];
}

int n;
pair<int, int> t[3 * 114514];
bool ok(int k) {
  ll sum = 0;
  priority_queue<int> q;
  for (int i = 0; i < k - 1; ++i) {
    sum += t[i].second;
    q.push(t[i].second);
  }

  for (int i = k - 1; i < n; ++i) {
    int a = t[i].second, b = t[i].first;
    if (sum + a <= b * k)
      return true;
    if (a < q.top()) {
      sum -= q.top();
      sum += a;
      q.pop();
      q.push(a);
    }
  }

  return false;
}
int main() {
  ios::sync_with_stdio(false);

  cin >> n;
  for (int i = 0; i < n; ++i)
    cin >> t[i].second >> t[i].first;
  sort(t, t + n, greater<pint>());

  int low = 0, high = n + 1;
  while (low + 1 < high) {
    int mid = (low + high) / 2;
    if (ok(mid))
      low = mid;
    else
      high = mid;
  }

  cout << low << endl;
}