Problem p02688 (C++) — buggy submission, verdict: Runtime Error

#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define INT(...)                                                               \\
  int __VA_ARGS__;                                                             \\
  in(__VA_ARGS__)
#define LL(...)                                                                \\
  ll __VA_ARGS__;                                                              \\
  in(__VA_ARGS__)
#define ULL(...)                                                               \\
  ull __VA_ARGS__;                                                             \\
  in(__VA_ARGS__)
#define STR(...)                                                               \\
  string __VA_ARGS__;                                                          \\
  in(__VA_ARGS__)
#define CHR(...)                                                               \\
  char __VA_ARGS__;                                                            \\
  in(__VA_ARGS__)
#define DBL(...)                                                               \\
  double __VA_ARGS__;                                                          \\
  in(__VA_ARGS__)
#define vec(type, name, ...) vector<type> name(__VA_ARGS__)
#define VEC(type, name, size)                                                  \\
  vector<type> name(size);                                                     \\
  in(name)
#define vv(type, name, h, ...)                                                 \\
  vector<vector<type>> name(h, vector<type>(__VA_ARGS__))
#define VV(type, name, h, ...)                                                 \\
  vector<vector<type>> name(h, vector<type>(__VA_ARGS__));                     \\
  in(name)
#define vvv(type, name, h, w, ...)                                             \\
  vector<vector<vector<type>>> name(                                           \\
      h, vector<vector<type>>(w, vector<type>(__VA_ARGS__)))
inline int scan() { return getchar(); }
inline void scan(int &a) { scanf("%d", &a); }
inline void scan(unsigned &a) { scanf("%u", &a); }
inline void scan(long &a) { scanf("%ld", &a); }
inline void scan(long long &a) { scanf("%lld", &a); }
inline void scan(unsigned long long &a) { scanf("%llu", &a); }
inline void scan(char &a) { cin >> a; }
inline void scan(float &a) { scanf("%f", &a); }
inline void scan(double &a) { scanf("%lf", &a); }
inline void scan(long double &a) { scanf("%Lf", &a); }
inline void scan(vector<bool> &vec) {
  for (unsigned i = 0; i < vec.size(); i++) {
    int a;
    scan(a);
    vec[i] = a;
  }
}
inline void scan(string &a) { cin >> a; }
template <class T> inline void scan(vector<T> &vec);
template <class T, size_t size> inline void scan(array<T, size> &vec);
template <class T, class L> inline void scan(pair<T, L> &p);
template <class T, size_t size> inline void scan(T (&vec)[size]);
template <class T> inline void scan(vector<T> &vec) {
  for (auto &i : vec)
    scan(i);
}
template <class T, size_t size> inline void scan(array<T, size> &vec) {
  for (auto &i : vec)
    scan(i);
}
template <class T, class L> inline void scan(pair<T, L> &p) {
  scan(p.first);
  scan(p.second);
}
template <class T, size_t size> inline void scan(T (&vec)[size]) {
  for (auto &i : vec)
    scan(i);
}
template <class T> inline void scan(T &a) { cin >> a; }
inline void in() {}
template <class Head, class... Tail> inline void in(Head &head, Tail &...tail) {
  scan(head);
  in(tail...);
}
inline constexpr ll gcd(ll a, ll b) {
  if (!a || !b)
    return 0;
  while (b) {
    ll c = b;
    b = a % b;
    a = c;
  }
  return a;
}
inline constexpr ll lcm(ll a, ll b) {
  if (!a || !b)
    return 0;
  return a * b / gcd(a, b);
}
template <class T> inline bool chmax(T &a, T b) {
  if (a < b) {
    a = b;
    return 1;
  }
  return 0;
}
template <class T> inline bool chmin(T &a, T b) {
  if (a > b) {
    a = b;
    return 1;
  }
  return 0;
}
using Graph = vector<vector<int>>;
/* 4方向への隣接頂点への移動を表すベクトル */
const int dx[4] = {1, 0, -1, 0};
const int dy[4] = {0, 1, 0, -1};

const long long INF = 1LL << 60;
int main() {
  INT(N);
  INT(K);
  vec(int, v, N);
  for (int i = 0; i < K; i++) {
    INT(d);
    for (int j = 0; j < d; j++) {
      int l = 0;
      cin >> l;
      v[l - 1]++;
    }
  }
  int ans = 0;
  for (int i = 0; i < N; i++) {
    if (v[i] == 0) {
      ans++;
    }
  }

  cout << ans << endl;
}

Error: 0

Fixed submission:

#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define INT(...)                                                               \\
  int __VA_ARGS__;                                                             \\
  in(__VA_ARGS__)
#define LL(...)                                                                \\
  ll __VA_ARGS__;                                                              \\
  in(__VA_ARGS__)
#define ULL(...)                                                               \\
  ull __VA_ARGS__;                                                             \\
  in(__VA_ARGS__)
#define STR(...)                                                               \\
  string __VA_ARGS__;                                                          \\
  in(__VA_ARGS__)
#define CHR(...)                                                               \\
  char __VA_ARGS__;                                                            \\
  in(__VA_ARGS__)
#define DBL(...)                                                               \\
  double __VA_ARGS__;                                                          \\
  in(__VA_ARGS__)
#define vec(type, name, ...) vector<type> name(__VA_ARGS__)
#define VEC(type, name, size)                                                  \\
  vector<type> name(size);                                                     \\
  in(name)
#define vv(type, name, h, ...)                                                 \\
  vector<vector<type>> name(h, vector<type>(__VA_ARGS__))
#define VV(type, name, h, ...)                                                 \\
  vector<vector<type>> name(h, vector<type>(__VA_ARGS__));                     \\
  in(name)
#define vvv(type, name, h, w, ...)                                             \\
  vector<vector<vector<type>>> name(                                           \\
      h, vector<vector<type>>(w, vector<type>(__VA_ARGS__)))
inline int scan() { return getchar(); }
inline void scan(int &a) { scanf("%d", &a); }
inline void scan(unsigned &a) { scanf("%u", &a); }
inline void scan(long &a) { scanf("%ld", &a); }
inline void scan(long long &a) { scanf("%lld", &a); }
inline void scan(unsigned long long &a) { scanf("%llu", &a); }
inline void scan(char &a) { cin >> a; }
inline void scan(float &a) { scanf("%f", &a); }
inline void scan(double &a) { scanf("%lf", &a); }
inline void scan(long double &a) { scanf("%Lf", &a); }
inline void scan(vector<bool> &vec) {
  for (unsigned i = 0; i < vec.size(); i++) {
    int a;
    scan(a);
    vec[i] = a;
  }
}
inline void scan(string &a) { cin >> a; }
template <class T> inline void scan(vector<T> &vec);
template <class T, size_t size> inline void scan(array<T, size> &vec);
template <class T, class L> inline void scan(pair<T, L> &p);
template <class T, size_t size> inline void scan(T (&vec)[size]);
template <class T> inline void scan(vector<T> &vec) {
  for (auto &i : vec)
    scan(i);
}
template <class T, size_t size> inline void scan(array<T, size> &vec) {
  for (auto &i : vec)
    scan(i);
}
template <class T, class L> inline void scan(pair<T, L> &p) {
  scan(p.first);
  scan(p.second);
}
template <class T, size_t size> inline void scan(T (&vec)[size]) {
  for (auto &i : vec)
    scan(i);
}
template <class T> inline void scan(T &a) { cin >> a; }
inline void in() {}
template <class Head, class... Tail> inline void in(Head &head, Tail &...tail) {
  scan(head);
  in(tail...);
}
inline constexpr ll gcd(ll a, ll b) {
  if (!a || !b)
    return 0;
  while (b) {
    ll c = b;
    b = a % b;
    a = c;
  }
  return a;
}
inline constexpr ll lcm(ll a, ll b) {
  if (!a || !b)
    return 0;
  return a * b / gcd(a, b);
}
template <class T> inline bool chmax(T &a, T b) {
  if (a < b) {
    a = b;
    return 1;
  }
  return 0;
}
template <class T> inline bool chmin(T &a, T b) {
  if (a > b) {
    a = b;
    return 1;
  }
  return 0;
}
using Graph = vector<vector<int>>;
/* 4方向への隣接頂点への移動を表すベクトル */
const int dx[4] = {1, 0, -1, 0};
const int dy[4] = {0, 1, 0, -1};

const long long INF = 1LL << 60;
int main() {
  INT(N);
  INT(K);
  vec(int, v, N - 1);
  for (int i = 0; i < K; i++) {
    INT(d);
    for (int j = 0; j < d; j++) {
      int l = 0;
      cin >> l;
      v[l - 1]++;
    }
  }
  int ans = 0;
  for (int i = 0; i < N; i++) {
    if (v[i] == 0) {
      ans++;
    }
  }

  cout << ans << endl;
}