Problem p02605 (C++)

Buggy submission (status: Runtime Error):
#include <algorithm>
#include <complex>
#include <cstdint>
#include <functional>
#include <iomanip>
#include <iostream>
#include <iterator>
#include <limits>
#include <list>
#include <map>
#include <math.h>
#include <queue>
#include <regex>
#include <set>
#include <stack>
#include <stdio.h>
#include <string>
#include <time.h>
#include <utility>
#include <vector>
using namespace std;
using pii = pair<int, int>;
using ll = long long;
using ld = long double;
#define pb push_back
#define mp make_pair
#define sc second
#define fr first
#define stpr setprecision
#define cYES cout << "YES" << endl
#define cNO cout << "NO" << endl
#define cYes cout << "Yes" << endl
#define cNo cout << "No" << endl
#define rep(i, n) for (ll i = 0; i < (n); ++i)
#define Rep(i, a, b) for (ll i = (a); i < (b); ++i)
#define rrep(i, n) for (ll i = n - 1; i >= 0; i--)
#define rRep(i, a, b) for (ll i = a; i >= b; i--)
#define crep(i) for (char i = 'a'; i <= 'z'; ++i)
#define psortsecond(A, N)                                                      \
  sort(A, A + N,                                                               \
       [](const pii &a, const pii &b) { return a.second < b.second; });
#define ALL(x) (x).begin(), (x).end()
#define debug(v)                                                               \
  cout << #v << ":";                                                           \
  for (auto x : v) {                                                           \
    cout << x << ' ';                                                          \
  }                                                                            \
  cout << endl;
#define endl '\n'
int ctoi(const char c) {
  if ('0' <= c && c <= '9')
    return (c - '0');
  return -1;
}
ll gcd(ll a, ll b) { return (b == 0 ? a : gcd(b, a % b)); }
ll lcm(ll a, ll b) { return a * b / gcd(a, b); }
constexpr ll MOD = 1000000007;
constexpr ll INF = 1000000011;
constexpr ll MOD2 = 998244353;
constexpr ll LINF = 1001002003004005006ll;
constexpr ld EPS = 10e-8;
template <class T, class U> inline bool chmax(T &lhs, const U &rhs) {
  if (lhs < rhs) {
    lhs = rhs;
    return 1;
  }
  return 0;
}
template <class T, class U> inline bool chmin(T &lhs, const U &rhs) {
  if (lhs > rhs) {
    lhs = rhs;
    return 1;
  }
  return 0;
}
template <typename T> istream &operator>>(istream &is, vector<T> &v) {
  for (auto &&x : v)
    is >> x;
  return is;
}
template <typename T, typename U>
istream &operator>>(istream &is, pair<T, U> &p) {
  is >> p.first;
  is >> p.second;
  return is;
}
template <typename T, typename U>
ostream &operator>>(ostream &os, const pair<T, U> &p) {
  os << p.first << ' ' << p.second;
  return os;
}
template <class T> ostream &operator<<(ostream &os, vector<T> &v) {
  for (auto i = begin(v); i != end(v); ++i) {
    if (i != begin(v))
      os << ' ';
    os << *i;
  }
  return os;
}

// modint

template <std::uint_fast64_t Modulus> class modint {
  using u64 = std::uint_fast64_t;

public:
  u64 a;

  constexpr modint(const u64 x = 0) noexcept : a(x % Modulus) {}
  constexpr u64 &value() noexcept { return a; }
  constexpr const u64 &value() const noexcept { return a; }
  constexpr modint operator+(const modint rhs) const noexcept {
    return modint(*this) += rhs;
  }
  constexpr modint operator-(const modint rhs) const noexcept {
    return modint(*this) -= rhs;
  }
  constexpr modint operator*(const modint rhs) const noexcept {
    return modint(*this) *= rhs;
  }
  constexpr modint operator/(const modint rhs) const noexcept {
    return modint(*this) /= rhs;
  }
  constexpr modint &operator+=(const modint rhs) noexcept {
    a += rhs.a;
    if (a >= Modulus) {
      a -= Modulus;
    }
    return *this;
  }
  constexpr modint &operator-=(const modint rhs) noexcept {
    if (a < rhs.a) {
      a += Modulus;
    }
    a -= rhs.a;
    return *this;
  }
  constexpr modint &operator*=(const modint rhs) noexcept {
    a = a * rhs.a % Modulus;
    return *this;
  }
  constexpr modint &operator/=(modint rhs) noexcept {
    u64 exp = Modulus - 2;
    while (exp) {
      if (exp % 2) {
        *this *= rhs;
      }
      rhs *= rhs;
      exp /= 2;
    }
    return *this;
  }
};

pair<pair<int, int>, char> P[20];
vector<set<int>> LU(800007), LD(800007), UL(800007), UR(800007), RU(800007),
    RD(800007), DL(800007), DR(800007), lU(800007), lD(800007), lL(800007),
    lR(800007);
int main() {
  int N;
  cin >> N;
  rep(i, N) { cin >> P[i].fr.fr >> P[i].fr.sc >> P[i].sc; }
  ll K = 400000;
  ll ANS = INF;
  rep(i, N) {
    ll X = P[i].fr.fr, Y = P[i].fr.sc;
    if (P[i].sc == 'U') {
      UL[X - Y + K].insert(X);
      UR[X + Y + K].insert(X);
      lU[X + K].insert(Y);
    }
    if (P[i].sc == 'D') {
      DR[X - Y + K].insert(X);
      DL[X + Y + K].insert(X);
      lD[X + K].insert(Y);
    }
    if (P[i].sc == 'L') {
      LU[X - Y + K].insert(X);
      LD[X + Y + K].insert(X);
      lL[Y + K].insert(X);
    }
    if (P[i].sc == 'R') {
      RD[X - Y + K].insert(X);
      RU[X + Y + K].insert(X);
      lR[Y + K].insert(X);
    }
    if (P[i].sc == 'U') {
      set<int>::iterator it1, it2, it3;
      if (lD[X + K].size() > 0) {
        it1 = lD[X + K].upper_bound(Y);
        if (it1 != lD[X + K].end()) {
          ANS = min(ANS, (*it1 - Y) * 5);
        }
      }
      if (LU[X - Y + K].size() > 0) {
        it2 = LU[X - Y + K].upper_bound(X);
        if (it2 != LU[X - Y + K].end()) {
          ANS = min(ANS, (*it2 - X) * 10);
        }
      }
      if (RU[X + Y + K].size() > 0) {
        it3 = RU[X + Y + K].lower_bound(X);
        if (it3 != RU[X + Y + K].begin()) {
          advance(it3, -1);
          ANS = min(ANS, (X - *it3) * 10);
        }
      }
    }
    if (P[i].sc == 'D') {
      set<int>::iterator it1, it2, it3;
      if (lU[X + K].size() > 0) {
        it1 = lU[X + K].lower_bound(Y);
        if (it1 != lU[X + K].begin()) {
          advance(it1, -1);
          ANS = min(ANS, (Y - *it1) * 5);
        }
      }
      if (RD[X - Y + K].size() > 0) {
        it2 = RD[X - Y + K].lower_bound(X);
        if (it2 != RD[X - Y + K].begin()) {
          advance(it2, -1);
          ANS = min(ANS, (X - *it2) * 10);
        }
      }
      if (LD[X + Y + K].size() > 0) {
        it3 = LD[X + Y + K].upper_bound(X);
        if (it3 != LD[X + Y + K].end()) {
          ANS = min(ANS, (*it3 - X) * 10);
        }
      }
    }
    if (P[i].sc == 'R') {
      set<int>::iterator it1, it2, it3;
      if (lL[Y + K].size() > 0) {
        it1 = lL[Y + K].upper_bound(X);
        if (it1 != lL[Y + K].end()) {
          ANS = min(ANS, (*it1 - X) * 5);
        }
      }
      if (DR[X - Y + K].size() > 0) {
        it2 = DR[X - Y + K].upper_bound(X);
        if (it2 != DR[X - Y + K].end()) {
          ANS = min(ANS, (*it2 - X) * 10);
        }
      }
      if (UR[X + Y + K].size() > 0) {
        it3 = UR[X + Y + K].upper_bound(X);
        if (it3 != UR[X + Y + K].end()) {
          ANS = min(ANS, (*it3 - X) * 10);
        }
      }
    }
    if (P[i].sc == 'L') {
      set<int>::iterator it1, it2, it3;
      if (lR[Y + K].size() > 0) {
        it1 = lR[Y + K].lower_bound(X);
        if (it1 != lR[Y + K].begin()) {
          advance(it1, -1);
          ANS = min(ANS, (X - *it1) * 5);
        }
      }
      if (UL[X - Y + K].size() > 0) {
        it2 = UL[X - Y + K].lower_bound(X);
        if (it2 != UL[X - Y + K].begin()) {
          advance(it2, -1);
          ANS = min(ANS, (X - *it2) * 10);
        }
      }
      if (DL[X + Y + K].size() > 0) {
        it3 = DL[X + Y + K].lower_bound(X);
        if (it3 != DL[X + Y + K].begin()) {
          advance(it3, -1);
          ANS = min(ANS, (X - *it3) * 10);
        }
      }
    }
    // cout << ANS << endl;
  }
  if (ANS == INF) {
    cout << "SAFE" << endl;
  } else {
    cout << ANS << endl;
  }
}

Fixed submission:
#include <algorithm>
#include <complex>
#include <cstdint>
#include <functional>
#include <iomanip>
#include <iostream>
#include <iterator>
#include <limits>
#include <list>
#include <map>
#include <math.h>
#include <queue>
#include <regex>
#include <set>
#include <stack>
#include <stdio.h>
#include <string>
#include <time.h>
#include <utility>
#include <vector>
using namespace std;
using pii = pair<int, int>;
using ll = long long;
using ld = long double;
#define pb push_back
#define mp make_pair
#define sc second
#define fr first
#define stpr setprecision
#define cYES cout << "YES" << endl
#define cNO cout << "NO" << endl
#define cYes cout << "Yes" << endl
#define cNo cout << "No" << endl
#define rep(i, n) for (ll i = 0; i < (n); ++i)
#define Rep(i, a, b) for (ll i = (a); i < (b); ++i)
#define rrep(i, n) for (ll i = n - 1; i >= 0; i--)
#define rRep(i, a, b) for (ll i = a; i >= b; i--)
#define crep(i) for (char i = 'a'; i <= 'z'; ++i)
#define psortsecond(A, N)                                                      \
  sort(A, A + N,                                                               \
       [](const pii &a, const pii &b) { return a.second < b.second; });
#define ALL(x) (x).begin(), (x).end()
#define debug(v)                                                               \
  cout << #v << ":";                                                           \
  for (auto x : v) {                                                           \
    cout << x << ' ';                                                          \
  }                                                                            \
  cout << endl;
#define endl '\n'
int ctoi(const char c) {
  if ('0' <= c && c <= '9')
    return (c - '0');
  return -1;
}
ll gcd(ll a, ll b) { return (b == 0 ? a : gcd(b, a % b)); }
ll lcm(ll a, ll b) { return a * b / gcd(a, b); }
constexpr ll MOD = 1000000007;
constexpr ll INF = 1000000011;
constexpr ll MOD2 = 998244353;
constexpr ll LINF = 1001002003004005006ll;
constexpr ld EPS = 10e-8;
template <class T, class U> inline bool chmax(T &lhs, const U &rhs) {
  if (lhs < rhs) {
    lhs = rhs;
    return 1;
  }
  return 0;
}
template <class T, class U> inline bool chmin(T &lhs, const U &rhs) {
  if (lhs > rhs) {
    lhs = rhs;
    return 1;
  }
  return 0;
}
template <typename T> istream &operator>>(istream &is, vector<T> &v) {
  for (auto &&x : v)
    is >> x;
  return is;
}
template <typename T, typename U>
istream &operator>>(istream &is, pair<T, U> &p) {
  is >> p.first;
  is >> p.second;
  return is;
}
template <typename T, typename U>
ostream &operator>>(ostream &os, const pair<T, U> &p) {
  os << p.first << ' ' << p.second;
  return os;
}
template <class T> ostream &operator<<(ostream &os, vector<T> &v) {
  for (auto i = begin(v); i != end(v); ++i) {
    if (i != begin(v))
      os << ' ';
    os << *i;
  }
  return os;
}

// modint

template <std::uint_fast64_t Modulus> class modint {
  using u64 = std::uint_fast64_t;

public:
  u64 a;

  constexpr modint(const u64 x = 0) noexcept : a(x % Modulus) {}
  constexpr u64 &value() noexcept { return a; }
  constexpr const u64 &value() const noexcept { return a; }
  constexpr modint operator+(const modint rhs) const noexcept {
    return modint(*this) += rhs;
  }
  constexpr modint operator-(const modint rhs) const noexcept {
    return modint(*this) -= rhs;
  }
  constexpr modint operator*(const modint rhs) const noexcept {
    return modint(*this) *= rhs;
  }
  constexpr modint operator/(const modint rhs) const noexcept {
    return modint(*this) /= rhs;
  }
  constexpr modint &operator+=(const modint rhs) noexcept {
    a += rhs.a;
    if (a >= Modulus) {
      a -= Modulus;
    }
    return *this;
  }
  constexpr modint &operator-=(const modint rhs) noexcept {
    if (a < rhs.a) {
      a += Modulus;
    }
    a -= rhs.a;
    return *this;
  }
  constexpr modint &operator*=(const modint rhs) noexcept {
    a = a * rhs.a % Modulus;
    return *this;
  }
  constexpr modint &operator/=(modint rhs) noexcept {
    u64 exp = Modulus - 2;
    while (exp) {
      if (exp % 2) {
        *this *= rhs;
      }
      rhs *= rhs;
      exp /= 2;
    }
    return *this;
  }
};

pair<pair<int, int>, char> P[200000];
vector<set<int>> LU(800007), LD(800007), UL(800007), UR(800007), RU(800007),
    RD(800007), DL(800007), DR(800007), lU(800007), lD(800007), lL(800007),
    lR(800007);
int main() {
  int N;
  cin >> N;
  rep(i, N) { cin >> P[i].fr.fr >> P[i].fr.sc >> P[i].sc; }
  ll K = 400000;
  ll ANS = INF;
  rep(i, N) {
    ll X = P[i].fr.fr, Y = P[i].fr.sc;
    if (P[i].sc == 'U') {
      UL[X - Y + K].insert(X);
      UR[X + Y + K].insert(X);
      lU[X + K].insert(Y);
    }
    if (P[i].sc == 'D') {
      DR[X - Y + K].insert(X);
      DL[X + Y + K].insert(X);
      lD[X + K].insert(Y);
    }
    if (P[i].sc == 'L') {
      LU[X - Y + K].insert(X);
      LD[X + Y + K].insert(X);
      lL[Y + K].insert(X);
    }
    if (P[i].sc == 'R') {
      RD[X - Y + K].insert(X);
      RU[X + Y + K].insert(X);
      lR[Y + K].insert(X);
    }
    if (P[i].sc == 'U') {
      set<int>::iterator it1, it2, it3;
      if (lD[X + K].size() > 0) {
        it1 = lD[X + K].upper_bound(Y);
        if (it1 != lD[X + K].end()) {
          ANS = min(ANS, (*it1 - Y) * 5);
        }
      }
      if (LU[X - Y + K].size() > 0) {
        it2 = LU[X - Y + K].upper_bound(X);
        if (it2 != LU[X - Y + K].end()) {
          ANS = min(ANS, (*it2 - X) * 10);
        }
      }
      if (RU[X + Y + K].size() > 0) {
        it3 = RU[X + Y + K].lower_bound(X);
        if (it3 != RU[X + Y + K].begin()) {
          advance(it3, -1);
          ANS = min(ANS, (X - *it3) * 10);
        }
      }
    }
    if (P[i].sc == 'D') {
      set<int>::iterator it1, it2, it3;
      if (lU[X + K].size() > 0) {
        it1 = lU[X + K].lower_bound(Y);
        if (it1 != lU[X + K].begin()) {
          advance(it1, -1);
          ANS = min(ANS, (Y - *it1) * 5);
        }
      }
      if (RD[X - Y + K].size() > 0) {
        it2 = RD[X - Y + K].lower_bound(X);
        if (it2 != RD[X - Y + K].begin()) {
          advance(it2, -1);
          ANS = min(ANS, (X - *it2) * 10);
        }
      }
      if (LD[X + Y + K].size() > 0) {
        it3 = LD[X + Y + K].upper_bound(X);
        if (it3 != LD[X + Y + K].end()) {
          ANS = min(ANS, (*it3 - X) * 10);
        }
      }
    }
    if (P[i].sc == 'R') {
      set<int>::iterator it1, it2, it3;
      if (lL[Y + K].size() > 0) {
        it1 = lL[Y + K].upper_bound(X);
        if (it1 != lL[Y + K].end()) {
          ANS = min(ANS, (*it1 - X) * 5);
        }
      }
      if (DR[X - Y + K].size() > 0) {
        it2 = DR[X - Y + K].upper_bound(X);
        if (it2 != DR[X - Y + K].end()) {
          ANS = min(ANS, (*it2 - X) * 10);
        }
      }
      if (UR[X + Y + K].size() > 0) {
        it3 = UR[X + Y + K].upper_bound(X);
        if (it3 != UR[X + Y + K].end()) {
          ANS = min(ANS, (*it3 - X) * 10);
        }
      }
    }
    if (P[i].sc == 'L') {
      set<int>::iterator it1, it2, it3;
      if (lR[Y + K].size() > 0) {
        it1 = lR[Y + K].lower_bound(X);
        if (it1 != lR[Y + K].begin()) {
          advance(it1, -1);
          ANS = min(ANS, (X - *it1) * 5);
        }
      }
      if (UL[X - Y + K].size() > 0) {
        it2 = UL[X - Y + K].lower_bound(X);
        if (it2 != UL[X - Y + K].begin()) {
          advance(it2, -1);
          ANS = min(ANS, (X - *it2) * 10);
        }
      }
      if (DL[X + Y + K].size() > 0) {
        it3 = DL[X + Y + K].lower_bound(X);
        if (it3 != DL[X + Y + K].begin()) {
          advance(it3, -1);
          ANS = min(ANS, (X - *it3) * 10);
        }
      }
    }
    // cout << ANS << endl;
  }
  if (ANS == INF) {
    cout << "SAFE" << endl;
  } else {
    cout << ANS << endl;
  }
}