Problem p02605 (C++) — buggy submission, verdict: Time Limit Exceeded

#include <bits/stdc++.h>
using namespace std;
#define LOCAL
#pragma region Macros
typedef long long ll;
#define ALL(x) (x).begin(), (x).end()
const long long MOD = 1e9 + 7;
// const long long MOD=998244353;
const int INF = 1e9;
const long long IINF = 1e18;
const int dx[4] = {1, 0, -1, 0}, dy[4] = {0, 1, 0, -1};
const char dir[4] = {'D', 'R', 'U', 'L'};

template <typename T> istream &operator>>(istream &is, vector<T> &v) {
  for (T &x : v)
    is >> x;
  return is;
}
template <typename T> ostream &operator<<(ostream &os, const vector<T> &v) {
  for (int i = 0; i < v.size(); ++i) {
    os << v[i] << (i + 1 == v.size() ? "" : " ");
  }
  return os;
}
template <typename T, typename U>
ostream &operator<<(ostream &os, const pair<T, U> &p) {
  cout << '(' << p.first << ',' << p.second << ')';
  return os;
}
template <typename T, typename U>
ostream &operator<<(ostream &os, const map<T, U> &m) {
  os << '{';
  for (auto itr = m.begin(); itr != m.end(); ++itr) {
    os << '(' << itr->first << ',' << itr->second << ')';
    if (++itr != m.end())
      os << ',';
    --itr;
  }
  os << '}';
  return os;
}
template <typename T> ostream &operator<<(ostream &os, const set<T> &s) {
  os << '{';
  for (auto itr = s.begin(); itr != s.end(); ++itr) {
    os << *itr;
    if (++itr != s.end())
      os << ',';
    --itr;
  }
  os << '}';
  return os;
}

void debug_out() { cerr << '\\n'; }
template <class Head, class... Tail>
void debug_out(Head &&head, Tail &&...tail) {
  cerr << head;
  if (sizeof...(Tail) > 0)
    cerr << ", ";
  debug_out(move(tail)...);
}
#ifdef LOCAL
#define debug(...)                                                             \\
  cerr << " ";                                                                 \\
  cerr << #__VA_ARGS__ << " :[" << __LINE__ << ":" << __FUNCTION__ << "]"      \\
       << '\\n';                                                                \\
  cerr << " ";                                                                 \\
  debug_out(__VA_ARGS__)
#else
#define debug(...) 42
#endif

template <typename T> T gcd(T x, T y) { return y != 0 ? gcd(y, x % y) : x; }
template <typename T> T lcm(T x, T y) { return x / gcd(x, y) * y; }

template <class T1, class T2> inline bool chmin(T1 &a, T2 b) {
  if (a > b) {
    a = b;
    return true;
  }
  return false;
}
template <class T1, class T2> inline bool chmax(T1 &a, T2 b) {
  if (a < b) {
    a = b;
    return true;
  }
  return false;
}
#pragma endregion

const int MAX_X = 2e5 + 10;

int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  int N;
  cin >> N;
  string URDL = "URDL";
  vector<vector<pair<int, int>>> pos(4);
  for (int i = 0; i < N; ++i) {
    int X, Y;
    char U;
    cin >> X >> Y >> U;
    for (int j = 0; j < 4; ++j) {
      if (U == URDL[j]) {
        if (j & 1)
          pos[j].emplace_back(X, Y);
        else
          pos[j].emplace_back(Y, X);
      }
    }
  }
  for (int i = 0; i < 4; ++i)
    sort(ALL(pos[i]));
  int ans = INF;
  map<int, vector<int>> uy, dy, rx, lx;
  for (auto p : pos[0])
    uy[p.second].emplace_back(p.first);
  for (auto p : pos[1])
    rx[p.second].emplace_back(p.first);
  for (auto p : pos[2])
    dy[p.second].emplace_back(p.first);
  for (auto p : pos[3])
    lx[p.second].emplace_back(p.first);
  /*
  for (int i=0;i<N;++i){
      if (U[i]=='U') uy[X[i]].emplace(Y[i]);
      if (U[i]=='R') rx[Y[i]].emplace(X[i]);
      if (U[i]=='D') dy[X[i]].emplace(Y[i]);
      if (U[i]=='L') lx[Y[i]].emplace(X[i]);
  }
  */
  for (auto p : uy) {
    if (!dy.count(p.first))
      continue;
    auto &v = dy[p.first];
    /*
    for (int y:p.second){
        auto itr=lower_bound(ALL(v),y);
        if (itr==v.end()) continue;
        chmin(ans,*itr-y);
    }
    */
    int s = v.size(), now = 0;
    for (int y : p.second) {
      while (now < s && v[now] < y)
        ++now;
      if (now == s)
        break;
      chmin(ans, v[now] - y);
    }
  }
  for (auto p : rx) {
    if (!lx.count(p.first))
      continue;
    auto &v = lx[p.first];
    /*
    for (int y:p.second){
        auto itr=lower_bound(ALL(v),y);
        if (itr==v.end()) continue;
        chmin(ans,*itr-y);
    }
    */
    int s = v.size(), now = 0;
    for (int y : p.second) {
      while (now < s && v[now] < y)
        ++now;
      if (now == s)
        break;
      chmin(ans, v[now] - y);
    }
  }
  for (int i = 0; i < pos[0].size(); ++i) {
    swap(pos[0][i].first, pos[0][i].second);
  }
  for (int i = 0; i < pos[2].size(); ++i) {
    swap(pos[2][i].first, pos[2][i].second);
  }
  sort(ALL(pos[0]));
  sort(ALL(pos[2]));
  vector<vector<map<int, vector<int>>>> naname(
      2, vector<map<int, vector<int>>>(4));
  for (int j = 0; j < 4; ++j) {
    for (auto p : pos[j]) {
      int X = p.first, Y = p.second;
      naname[0][j][X + Y].emplace_back(X);
      naname[1][j][X - Y].emplace_back(X);
    }
  }
  /*
  for (int i=0;i<N;++i){
      for (int j=0;j<4;++j){
          if (U[i]==URDL[j]){
              naname[0][j][X[i]+Y[i]].emplace(X[i]);
              naname[1][j][X[i]-Y[i]].emplace(X[i]);
          }
      }
  }
  */
  for (int i = 0; i < 2; ++i) {
    for (int j = 0; j <= 2; j += 2) {
      for (auto p : naname[i][j]) {
        if (naname[i][1].count(p.first)) {
          auto &v = naname[i][1][p.first];
          int s = v.size(), now = -1;
          for (int x : p.second) {
            if (i == 0 && j == 0) {
              /*
              auto itr=upper_bound(ALL(v),x);
              if (itr==v.begin()) continue;
              chmin(ans,2*(x-*(--itr)));
              */
              while (now + 1 < s && v[now + 1] <= x)
                ++now;
              if (now < 0)
                continue;
              chmin(ans, 2 * (x - v[now]));
            }
            if (i == 1 && j == 2) {
              /*
              auto itr=upper_bound(ALL(v),x);
              if (itr==v.begin()) continue;
              chmin(ans,2*(x-*(--itr)));
              */
              while (now + 1 < s && v[now + 1] <= x)
                ++now;
              if (now < 0)
                continue;
              chmin(ans, 2 * (x - v[now]));
            }
          }
        }
        if (naname[i][3].count(p.first)) {
          auto &v = naname[i][3][p.first];
          int s = v.size(), now = 0;
          for (int x : p.second) {
            if (i == 0 && j == 2) {
              /*
              auto itr=lower_bound(ALL(v),x);
              if (itr==v.end()) continue;
              chmin(ans,2*(*itr-x));
              */
              while (now < s && v[now] < x)
                ++now;
              if (now == s)
                break;
              chmin(ans, 2 * (v[now] - x));
            }
            if (i == 1 && j == 0) {
              /*
              auto itr=lower_bound(ALL(v),x);
              if (itr==v.end()) continue;
              chmin(ans,2*(*itr-x));
              */
              while (now < s && v[now] < x)
                ++now;
              if (now == s)
                break;
              chmin(ans, 2 * (v[now] - x));
            }
          }
        }
      }
    }
  }
  if (ans == INF)
    cout << "SAFE" << '\\n';
  else
    cout << ans * 5 << '\\n';
}

Error: TLE

Fixed submission:

#include <bits/stdc++.h>
using namespace std;
#define LOCAL
#pragma region Macros
typedef long long ll;
#define ALL(x) (x).begin(), (x).end()
const long long MOD = 1e9 + 7;
// const long long MOD=998244353;
const int INF = 1e9;
const long long IINF = 1e18;
const int dx[4] = {1, 0, -1, 0}, dy[4] = {0, 1, 0, -1};
const char dir[4] = {'D', 'R', 'U', 'L'};

template <typename T> istream &operator>>(istream &is, vector<T> &v) {
  for (T &x : v)
    is >> x;
  return is;
}
template <typename T> ostream &operator<<(ostream &os, const vector<T> &v) {
  for (int i = 0; i < v.size(); ++i) {
    os << v[i] << (i + 1 == v.size() ? "" : " ");
  }
  return os;
}
template <typename T, typename U>
ostream &operator<<(ostream &os, const pair<T, U> &p) {
  cout << '(' << p.first << ',' << p.second << ')';
  return os;
}
template <typename T, typename U>
ostream &operator<<(ostream &os, const map<T, U> &m) {
  os << '{';
  for (auto itr = m.begin(); itr != m.end(); ++itr) {
    os << '(' << itr->first << ',' << itr->second << ')';
    if (++itr != m.end())
      os << ',';
    --itr;
  }
  os << '}';
  return os;
}
template <typename T> ostream &operator<<(ostream &os, const set<T> &s) {
  os << '{';
  for (auto itr = s.begin(); itr != s.end(); ++itr) {
    os << *itr;
    if (++itr != s.end())
      os << ',';
    --itr;
  }
  os << '}';
  return os;
}

void debug_out() { cerr << '\\n'; }
template <class Head, class... Tail>
void debug_out(Head &&head, Tail &&...tail) {
  cerr << head;
  if (sizeof...(Tail) > 0)
    cerr << ", ";
  debug_out(move(tail)...);
}
#ifdef LOCAL
#define debug(...)                                                             \\
  cerr << " ";                                                                 \\
  cerr << #__VA_ARGS__ << " :[" << __LINE__ << ":" << __FUNCTION__ << "]"      \\
       << '\\n';                                                                \\
  cerr << " ";                                                                 \\
  debug_out(__VA_ARGS__)
#else
#define debug(...) 42
#endif

template <typename T> T gcd(T x, T y) { return y != 0 ? gcd(y, x % y) : x; }
template <typename T> T lcm(T x, T y) { return x / gcd(x, y) * y; }

template <class T1, class T2> inline bool chmin(T1 &a, T2 b) {
  if (a > b) {
    a = b;
    return true;
  }
  return false;
}
template <class T1, class T2> inline bool chmax(T1 &a, T2 b) {
  if (a < b) {
    a = b;
    return true;
  }
  return false;
}
#pragma endregion

const int MAX_X = 2e5 + 10;

int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  int N;
  cin >> N;
  vector<int> X(N), Y(N);
  vector<char> U(N);
  for (int i = 0; i < N; ++i)
    cin >> X[i] >> Y[i] >> U[i];
  int ans = INF;
  map<int, set<int>> uy, dy, rx, lx;
  for (int i = 0; i < N; ++i) {
    if (U[i] == 'U')
      uy[X[i]].emplace(Y[i]);
    if (U[i] == 'R')
      rx[Y[i]].emplace(X[i]);
    if (U[i] == 'D')
      dy[X[i]].emplace(Y[i]);
    if (U[i] == 'L')
      lx[Y[i]].emplace(X[i]);
  }
  for (auto p : uy) {
    if (!dy.count(p.first))
      continue;
    auto &v = dy[p.first];
    for (int y : p.second) {
      auto itr = lower_bound(ALL(v), y);
      if (itr == v.end())
        continue;
      chmin(ans, *itr - y);
    }
  }
  for (auto p : rx) {
    if (!lx.count(p.first))
      continue;
    auto &v = lx[p.first];
    for (int y : p.second) {
      auto itr = lower_bound(ALL(v), y);
      if (itr == v.end())
        continue;
      chmin(ans, *itr - y);
    }
  }
  vector<vector<map<int, set<int>>>> naname(2, vector<map<int, set<int>>>(4));
  string URDL = "URDL";
  for (int i = 0; i < N; ++i) {
    for (int j = 0; j < 4; ++j) {
      if (U[i] == URDL[j]) {
        naname[0][j][X[i] + Y[i]].emplace(X[i]);
        naname[1][j][X[i] - Y[i]].emplace(X[i]);
      }
    }
  }
  for (int i = 0; i < 2; ++i) {
    for (int j = 0; j <= 2; j += 2) {
      for (auto p : naname[i][j]) {
        if (naname[i][1].count(p.first)) {
          for (int x : p.second) {
            auto &v = naname[i][1][p.first];
            if (i == 0 && j == 0) {
              auto itr = upper_bound(ALL(v), x);
              if (itr == v.begin())
                continue;
              chmin(ans, 2 * (x - *(--itr)));
            }
            if (i == 1 && j == 2) {
              auto itr = upper_bound(ALL(v), x);
              if (itr == v.begin())
                continue;
              chmin(ans, 2 * (x - *(--itr)));
            }
          }
        }
        if (naname[i][3].count(p.first)) {
          for (int x : p.second) {
            auto &v = naname[i][3][p.first];
            if (i == 0 && j == 2) {
              auto itr = lower_bound(ALL(v), x);
              if (itr == v.end())
                continue;
              chmin(ans, 2 * (*itr - x));
            }
            if (i == 1 && j == 0) {
              auto itr = lower_bound(ALL(v), x);
              if (itr == v.end())
                continue;
              chmin(ans, 2 * (*itr - x));
            }
          }
        }
      }
    }
  }
  if (ans == INF)
    cout << "SAFE" << '\\n';
  else
    cout << ans * 5 << '\\n';
}