Problem p00368 (C++) — buggy submission, verdict: Runtime Error

#include <bits/stdc++.h>
#define rep(i, n) for (int i = 0; i < (int)n; i++)
#define all(c) (c).begin(), (c).end()
#define pb push_back
#define dbg(...)                                                               \\
  do {                                                                         \\
    cerr << __LINE__ << ": ";                                                  \\
    dbgprint(#__VA_ARGS__, __VA_ARGS__);                                       \\
  } while (0);

using namespace std;

namespace std {
template <class S, class T> struct hash<pair<S, T>> {
  size_t operator()(const pair<S, T> &p) const {
    return ((size_t)1e9 + 7) * hash<S>()(p.first) + hash<T>()(p.second);
  }
};
template <class T> struct hash<vector<T>> {
  size_t operator()(const vector<T> &v) const {
    size_t h = 0;
    for (auto i : v)
      h = h * ((size_t)1e9 + 7) + hash<T>()(i) + 1;
    return h;
  }
};
} // namespace std
template <class T> ostream &operator<<(ostream &os, const vector<T> &v) {
  os << "[ ";
  rep(i, v.size()) os << v[i] << (i == v.size() - 1 ? " ]" : ", ");
  return os;
}
template <class T> ostream &operator<<(ostream &os, const set<T> &v) {
  os << "{ ";
  for (const auto &i : v)
    os << i << ", ";
  return os << "}";
}
template <class T, class U>
ostream &operator<<(ostream &os, const map<T, U> &v) {
  os << "{";
  for (const auto &i : v)
    os << " " << i.first << ": " << i.second << ",";
  return os << "}";
}
template <class T, class U>
ostream &operator<<(ostream &os, const pair<T, U> &p) {
  return os << "(" << p.first << ", " << p.second << ")";
}
void dbgprint(const string &fmt) { cerr << endl; }
template <class H, class... T>
void dbgprint(const string &fmt, const H &h, const T &...r) {
  cerr << fmt.substr(0, fmt.find(",")) << "= " << h << " ";
  dbgprint(fmt.substr(fmt.find(",") + 1), r...);
}
typedef long long ll;
typedef vector<int> vi;
typedef pair<int, int> pi;
const int inf = (int)1e9;
const double INF = 1e12, EPS = 1e-9;

vector<vi> transpose(const vector<vi> &a) {
  vector<vi> b(a[0].size(), vi(a.size()));
  rep(i, a.size()) rep(j, a[0].size()) b[j][i] = a[i][j];
  return b;
}
bool check(vector<vi> a) {
  while (1) {
    vector<vi> x = a;
    rep(it, 2) {
      sort(all(a));
      a = transpose(a);
    }
    if (x == a)
      break;
  }
  // rep(i, a.size()) rep(j, a[0].size())
  // cerr<<a[i][j]<<(j==a[0].size()-1?"\\n":"");
  int h = (a.size() + 1) / 2, w = (a[0].size() + 1) / 2;
  rep(it, 2) {
    vector<vi> x = a;
    rep(i, a.size()) rep(j, a[0].size()) {
      int v = (i < h) ^ (j < w);
      if (v != a[i][j])
        goto FAIL;
    }
    return 1;
  FAIL:;
    rep(i, a.size()) rep(j, a[0].size())
        a[a.size() - 1 - i][a[0].size() - 1 - j] = x[i][j];
  }
  return 0;
}

int main() {
  cin.tie(0);
  cin.sync_with_stdio(0);
  int w, h;
  cin >> w >> h;
  vector<vi> a(h, vi(w));
  // rep(i, h) rep(j, w) a[i][j] = (i + j) & 1;

  int cnt = 0;
  rep(i, h) rep(j, w) {
    cin >> a[i][j];
    cnt += a[i][j];
  }
  if (2 * cnt > h * w)
    rep(i, h) rep(j, w) a[i][j] ^= 1;

  cout << (check(a) ? "yes" : "no") << endl;
  return 0;
}


Error: 0
001
110


Fixed submission:

#include <bits/stdc++.h>
#define rep(i, n) for (int i = 0; i < (int)n; i++)
#define all(c) (c).begin(), (c).end()
#define pb push_back
#define dbg(...)                                                               \\
  do {                                                                         \\
    cerr << __LINE__ << ": ";                                                  \\
    dbgprint(#__VA_ARGS__, __VA_ARGS__);                                       \\
  } while (0);

using namespace std;

namespace std {
template <class S, class T> struct hash<pair<S, T>> {
  size_t operator()(const pair<S, T> &p) const {
    return ((size_t)1e9 + 7) * hash<S>()(p.first) + hash<T>()(p.second);
  }
};
template <class T> struct hash<vector<T>> {
  size_t operator()(const vector<T> &v) const {
    size_t h = 0;
    for (auto i : v)
      h = h * ((size_t)1e9 + 7) + hash<T>()(i) + 1;
    return h;
  }
};
} // namespace std
template <class T> ostream &operator<<(ostream &os, const vector<T> &v) {
  os << "[ ";
  rep(i, v.size()) os << v[i] << (i == v.size() - 1 ? " ]" : ", ");
  return os;
}
template <class T> ostream &operator<<(ostream &os, const set<T> &v) {
  os << "{ ";
  for (const auto &i : v)
    os << i << ", ";
  return os << "}";
}
template <class T, class U>
ostream &operator<<(ostream &os, const map<T, U> &v) {
  os << "{";
  for (const auto &i : v)
    os << " " << i.first << ": " << i.second << ",";
  return os << "}";
}
template <class T, class U>
ostream &operator<<(ostream &os, const pair<T, U> &p) {
  return os << "(" << p.first << ", " << p.second << ")";
}
void dbgprint(const string &fmt) { cerr << endl; }
template <class H, class... T>
void dbgprint(const string &fmt, const H &h, const T &...r) {
  cerr << fmt.substr(0, fmt.find(",")) << "= " << h << " ";
  dbgprint(fmt.substr(fmt.find(",") + 1), r...);
}
typedef long long ll;
typedef vector<int> vi;
typedef pair<int, int> pi;
const int inf = (int)1e9;
const double INF = 1e12, EPS = 1e-9;

vector<vi> transpose(const vector<vi> &a) {
  vector<vi> b(a[0].size(), vi(a.size()));
  rep(i, a.size()) rep(j, a[0].size()) b[j][i] = a[i][j];
  return b;
}
bool check(vector<vi> a) {
  while (1) {
    vector<vi> x = a;
    rep(it, 2) {
      sort(all(a));
      a = transpose(a);
    }
    if (x == a)
      break;
  }
  rep(i, a.size()) rep(j, a[0].size()) cerr
      << a[i][j] << (j == a[0].size() - 1 ? "\\n" : "");
  int h = (a.size() + 1) / 2, w = (a[0].size() + 1) / 2;
  rep(i, a.size()) rep(j, a[0].size()) {
    int x = (i < h) ^ (j < w);
    if (x != a[i][j])
      return 0;
  }
  return 1;
}

int main() {
  cin.tie(0);
  cin.sync_with_stdio(0);
  int w, h;
  cin >> w >> h;
  vector<vi> a(h, vi(w));
  // rep(i, h) rep(j, w) a[i][j] = (i + j) & 1;

  int cnt = 0;
  rep(i, h) rep(j, w) {
    cin >> a[i][j];
    cnt += a[i][j];
  }
  if (2 * cnt > h * w)
    rep(i, h) rep(j, w) a[i][j] ^= 1;

  cout << (check(a) ? "yes" : "no") << endl;
  return 0;
}