Problem p02557 (C++) — buggy submission, verdict: Time Limit Exceeded

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

inline unsigned long long xor128() {
  static unsigned long long x = 123456789;
  static unsigned long long y = 362436069;
  static unsigned long long z = 521288629;
  static unsigned long long w = 88675123;
  unsigned long long t = x ^ (x << 11);
  x = y;
  y = z;
  z = w;
  return w = (w ^ (w >> 19)) ^ (t ^ (t >> 8));
}

int main() {
  ll N;
  cin >> N;
  vector<ll> a(N), b(N);
  for (ll i = 0; i < N; i++)
    cin >> a[i];
  for (ll i = 0; i < N; i++)
    cin >> b[i];

  map<ll, ll> am, bm;
  for (ll i = 0; i < N; i++) {
    am[a[i]]++;
    bm[b[i]]++;
  }
  for (auto &&pr : am) {
    if (pr.second + bm[pr.first] > N) {
      cout << "No\\n";
      return 0;
    }
  }

  std::random_device seed_gen;
  std::mt19937 engine(seed_gen());
  shuffle(b.begin(), b.end(), engine);

  // shuffleの代わりにreverseもよさそう
  // reverse(b.begin(), b.end());

  ll i = 0, j = N - 1;
  while (i < j) {
    while (i < N && a[i] != b[i])
      i++;
    while (j >= 0 && a[i] == b[i])
      j--;
    if (i < j) {
      swap(a[i], a[j]);
      swap(b[i], b[j]);
    }
  }

  while (i < N) {
    ll r = xor128() % (N - 1);
    if (r >= i)
      r++;
    swap(b[i], b[r]);
    if (r < i) {
      if (a[i] == b[i] && a[r] == b[r]) {
        i--;
        swap(a[i], a[r]);
        swap(b[i], b[r]);
      } else if (a[i] != b[i] && a[r] != b[r]) {
        i++;
      } else if (a[r] != b[r]) {
        ;
      } else if (a[i] != b[i]) {
        swap(a[i], a[r]);
        swap(b[i], b[r]);
      }
    } else {
      if (a[i] == b[i] && a[r] == b[r]) {
        ;
      } else if (a[i] != b[i] && a[r] != b[r]) {
        i++;
        swap(a[i], a[r]);
        swap(b[i], b[r]);
      } else if (a[r] != b[r]) {
        swap(a[i], a[r]);
        swap(b[i], b[r]);
      } else if (a[i] != b[i]) {
        ;
      }
    }
  }

  vector<pair<ll, ll>> ans(N);
  for (ll i = 0; i < N; i++) {
    ans[i] = {a[i], b[i]};
  }

  sort(ans.begin(), ans.end());
  cout << "Yes\\n";
  for (ll i = 0; i < N; i++)
    cout << ans[i].second << " \\n"[i == N - 1];

  return 0;
}


Error: TLE

Fixed submission:

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

#ifdef LOCAL_TEST
#define BOOST_STACKTRACE_USE_ADDR2LINE
#define BOOST_STACKTRACE_ADDR2LINE_LOCATION                                    \\
  / usr / local / opt / binutils / bin / addr2line
#define _GNU_SOURCE 1
#include <boost/stacktrace.hpp>
namespace std {
template <typename T> class dvector : public std::vector<T> {
public:
  dvector() : std::vector<T>() {}
  explicit dvector(size_t n, const T &value = T()) : std::vector<T>(n, value) {}
  dvector(const std::vector<T> &v) : std::vector<T>(v) {}
  dvector(const std::initializer_list<T> il) : std::vector<T>(il) {}
  dvector(const std::string::iterator first, const std::string::iterator last)
      : std::vector<T>(first, last) {}
  dvector(const typename std::vector<T>::iterator first,
          const typename std::vector<T>::iterator last)
      : std::vector<T>(first, last) {}
  dvector(const typename std::vector<T>::reverse_iterator first,
          const typename std::vector<T>::reverse_iterator last)
      : std::vector<T>(first, last) {}
  dvector(const typename std::vector<T>::const_iterator first,
          const typename std::vector<T>::const_iterator last)
      : std::vector<T>(first, last) {}
  dvector(const typename std::vector<T>::const_reverse_iterator first,
          const typename std::vector<T>::const_reverse_iterator last)
      : std::vector<T>(first, last) {}
  T &operator[](size_t n) {
    try {
      return this->at(n);
    } catch (const std::exception &e) {
      std::cerr << boost::stacktrace::stacktrace() << '\\n';
      return this->at(n);
    }
  }
  const T &operator[](size_t n) const {
    try {
      return this->at(n);
    } catch (const std::exception &e) {
      std::cerr << boost::stacktrace::stacktrace() << '\\n';
      return this->at(n);
    }
  }
};
} // namespace std
class dbool {
private:
  bool boolvalue;

public:
  dbool() : boolvalue(false) {}
  dbool(bool b) : boolvalue(b) {}
  operator bool &() { return boolvalue; }
  operator const bool &() const { return boolvalue; }
};
#define vector dvector
#define bool dbool
class SIGFPE_exception : std::exception {};
class SIGSEGV_exception : std::exception {};
void catch_SIGFPE([[maybe_unused]] int e) {
  std::cerr << boost::stacktrace::stacktrace() << '\\n';
  throw SIGFPE_exception();
}
void catch_SIGSEGV([[maybe_unused]] int e) {
  std::cerr << boost::stacktrace::stacktrace() << '\\n';
  throw SIGSEGV_exception();
}
signed convertedmain();
signed main() {
  signal(SIGFPE, catch_SIGFPE);
  signal(SIGSEGV, catch_SIGSEGV);
  return convertedmain();
}
#define main() convertedmain()
#endif
#ifdef LOCAL_DEV
template <typename T1, typename T2>
std::ostream &operator<<(std::ostream &s, const std::pair<T1, T2> &p) {
  return s << "(" << p.first << ", " << p.second << ")";
}
template <typename T, size_t N>
std::ostream &operator<<(std::ostream &s, const std::array<T, N> &a) {
  s << "{ ";
  for (size_t i = 0; i < N; ++i) {
    s << a[i] << "\\t";
  }
  s << "}";
  return s;
}
template <typename T>
std::ostream &operator<<(std::ostream &s, const std::set<T> &se) {
  s << "{ ";
  for (auto itr = se.begin(); itr != se.end(); ++itr) {
    s << (*itr) << "\\t";
  }
  s << "}";
  return s;
}
template <typename T>
std::ostream &operator<<(std::ostream &s, const std::multiset<T> &se) {
  s << "{ ";
  for (auto itr = se.begin(); itr != se.end(); ++itr) {
    s << (*itr) << "\\t";
  }
  s << "}";
  return s;
}
template <typename T1, typename T2>
std::ostream &operator<<(std::ostream &s, const std::map<T1, T2> &m) {
  s << "{\\n";
  for (auto itr = m.begin(); itr != m.end(); ++itr) {
    s << "\\t" << (*itr).first << " : " << (*itr).second << "\\n";
  }
  s << "}";
  return s;
}
template <typename T>
std::ostream &operator<<(std::ostream &s, const std::deque<T> &v) {
  for (size_t i = 0; i < v.size(); ++i) {
    s << v[i];
    if (i < v.size() - 1)
      s << "\\t";
  }
  return s;
}
template <typename T>
std::ostream &operator<<(std::ostream &s, const std::vector<T> &v) {
  for (size_t i = 0; i < v.size(); ++i) {
    s << v[i];
    if (i < v.size() - 1)
      s << "\\t";
  }
  return s;
}
template <typename T>
std::ostream &operator<<(std::ostream &s,
                         const std::vector<std::vector<T>> &vv) {
  s << "\\\\\\n";
  for (size_t i = 0; i < vv.size(); ++i) {
    s << vv[i] << "\\n";
  }
  return s;
}
void debug_impl() { std::cerr << '\\n'; }
template <typename Head, typename... Tail>
void debug_impl(Head head, Tail... tail) {
  std::cerr << " " << head << (sizeof...(tail) ? "," : "");
  debug_impl(tail...);
}
#define debug(...)                                                             \\
  do {                                                                         \\
    std::cerr << ":" << __LINE__ << " (" << #__VA_ARGS__ << ") =";             \\
    debug_impl(__VA_ARGS__);                                                   \\
  } while (false)
#else
#define debug(...)                                                             \\
  do {                                                                         \\
  } while (false)
#endif

inline unsigned long long xor128() {
  static unsigned long long x = 123456789;
  static unsigned long long y = 362436069;
  static unsigned long long z = 521288629;
  static unsigned long long w = 88675123;
  unsigned long long t = x ^ (x << 11);
  x = y;
  y = z;
  z = w;
  return w = (w ^ (w >> 19)) ^ (t ^ (t >> 8));
}

int main() {
  ll N;
  cin >> N;
  vector<ll> a(N), b(N);
  for (ll i = 0; i < N; i++)
    cin >> a[i];
  for (ll i = 0; i < N; i++)
    cin >> b[i];

  map<ll, ll> am, bm;
  for (ll i = 0; i < N; i++) {
    am[a[i]]++;
    bm[b[i]]++;
  }
  for (auto &&pr : am) {
    if (pr.second + bm[pr.first] > N) {
      cout << "No\\n";
      return 0;
    }
  }

  std::random_device seed_gen;
  std::mt19937 engine(seed_gen());
  shuffle(b.begin(), b.end(), engine);

  // shuffleの代わりにreverseもよさそう
  // reverse(b.begin(), b.end());

  ll i = 0, j = N - 1;
  while (i < j) {
    while (i < N && a[i] != b[i])
      i++;
    while (j >= 0 && a[i] == b[i])
      j--;
    if (i < j) {
      swap(a[i], a[j]);
      swap(b[i], b[j]);
    }
  }
  debug(i, j);
  while (i < N) {
    debug(a);
    debug(b);
    ll r = xor128() % (N - 1);
    debug(i, r);
    if (r >= i)
      r++;
    swap(b[i], b[r]);
    if (r < i) {
      if (a[i] == b[i] && a[r] == b[r]) {
        i--;
        swap(a[i], a[r]);
        swap(b[i], b[r]);
      } else if (a[i] != b[i] && a[r] != b[r]) {
        i++;
      } else if (a[r] != b[r]) {
        ;
      } else if (a[i] != b[i]) {
        swap(a[i], a[r]);
        swap(b[i], b[r]);
      }
    } else {
      if (a[i] == b[i] && a[r] == b[r]) {
        ;
      } else if (a[i] != b[i] && a[r] != b[r]) {
        i++;
        swap(a[i], a[r]);
        swap(b[i], b[r]);
      } else if (a[r] != b[r]) {
        swap(a[i], a[r]);
        swap(b[i], b[r]);
      } else if (a[i] != b[i]) {
        ;
      }
    }
  }

  vector<pair<ll, ll>> ans(N);
  for (ll i = 0; i < N; i++) {
    ans[i] = {a[i], b[i]};
  }
  debug(a);
  debug(b);

  sort(ans.begin(), ans.end());
  cout << "Yes\\n";
  for (ll i = 0; i < N; i++)
    cout << ans[i].second << " \\n"[i == N - 1];

  return 0;
}