#line 1 "F.cpp"
#include <cstdio>
#include <cstdint>
#include <cstdlib>
#include <algorithm>
#include <array>
#include <map>
#include <set>
#include <string>
#include <tuple>
#include <utility>
#include <vector>

#line 1 "~/git/library/utility/io.cpp"



/**
 * @brief 入出力
 * @author えびちゃん
 */

#include <cstddef>
#include <cctype>
#include <iomanip>
#include <iostream>
#line 15 "~/git/library/utility/io.cpp"

class format {
public:
  using size_type = size_t;

private:
  char const* M_fmt;
  size_type M_nvars = 0;
  size_type M_error = -1;

  void M_print(std::ostream& os, char const* pos) const {
    while (*pos) {
      if (*pos == '{' || *pos == '}') ++pos;
      os << *pos++;
    }
  }

  template <typename Tp, typename... Args>
  void M_print(std::ostream& os, char const* pos, Tp const& x, Args const&... xs) const {
    while (true) {
      if (*pos == '{') {
        if (pos[1] == '{') {
          ++pos;
          os << '{';
        } else {
          char const* next = M_print_formatted(os, pos, x);
          return M_print(os, next, xs...);
        }
      } else {
        if (*pos == '}') ++pos;
        os << *pos;
      }
      ++pos;
    }
    char const* next = M_print_formatted(os, pos, x);
    M_print(os, next, xs...);
  }

  template <typename Tp>
  char const* M_print_formatted(std::ostream& os, char const* pos, Tp const& x) const {
    // parse flags, preferably
    while (*++pos != '}') {}
    os << x;
    return ++pos;
  }

  void M_scan(std::istream& is, char const* pos) const {
    while (true) {
      if (*pos == '{' || *pos == '}') ++pos;
      if (isspace(*pos)) {
        while (isspace(is.peek())) is.get();
      } else {
        if (is.peek() == *pos) {
          ++pos;
          is.get();
        } else {
          return;
        }
      }
    }
  }

  template <typename Tp, typename... Args>
  void M_scan(std::istream& is, char const* pos, Tp& x, Args&&... xs) const {
    while (true) {
      if (*pos == '{') {
        if (pos[1] == '{') {
          if (is.peek() == '{') {
            ++pos;
            is.get();
          } else {
            return;
          }
        } else {
          char const* next = M_scan_formatted(is, pos, x);
          return M_scan(is, next, xs...);
        }
      } else if (isspace(*pos)) {
        while (isspace(is.peek())) is.get();
        ++pos;
      } else {
        if (*pos == '}') ++pos;
        if (is.peek() == *pos) {
          ++pos;
          is.get();
        } else {
          return;
        }
      }
    }
  }

  template <typename Tp>
  char const* M_scan_formatted(std::istream& is, char const* pos, Tp& x) const {
    // parse flags, preferably
    while (*++pos != '}') {}
    is >> x;
    return ++pos;
  }

public:
  constexpr format(char const* fmt): M_fmt(fmt) {
    bool opens = 0;
    size_type i = 0;
    for (; fmt[i]; ++i) {
      if (fmt[i] == '{') {
        if (fmt[i+1] == '{') { ++i; continue; }  // escaped
        if (opens) { M_error = i; return; }
        opens = true;
      } else if (fmt[i] == '}') {
        if (fmt[i+1] == '}') { ++i; continue; }  // escaped
        if (!opens) { M_error = i; return; }
        opens = false;
        ++M_nvars;
      }
    }
    if (opens) { M_error = i; return; }
  }

  template <typename... Args>
  void print_(std::ostream& os, Args const&... xs) const {
    M_print(os, M_fmt, xs...);
  }

  template <typename... Args>
  void scan_(std::istream& is, Args&&... xs) const {
    M_scan(is, M_fmt, xs...);
  }

  constexpr size_type count() const { return M_nvars; }
  constexpr size_type error() const { return M_error; }
};

#define VA_COUNT(...)                                           \
  std::tuple_size<decltype(std::make_tuple(__VA_ARGS__))>::value

#define fprint(os, fmt, ...) (void)({                           \
      constexpr format fmt_(fmt);                               \
      constexpr size_t lhs = fmt_.count();                      \
      constexpr size_t rhs = VA_COUNT(__VA_ARGS__);             \
      static_assert(lhs == rhs, "size mismatch");               \
      static_assert(fmt_.error()+1 == 0, "misformatted");       \
      fmt_.print_(os, ##__VA_ARGS__);                           \
    })

#define fprintln(os, fmt, ...) (void)({         \
      fprint(os, fmt, ##__VA_ARGS__);           \
      os << '\n';;                              \
    })

#define print(...) fprint(std::cout, ##__VA_ARGS__)
#define println(...) fprintln(std::cout, ##__VA_ARGS__)
#define eprint(...) fprint(std::cerr, ##__VA_ARGS__)
#define eprintln(...) fprintln(std::cerr, ##__VA_ARGS__)

#define fscan(is, fmt, ...) (void)({                            \
      constexpr format fmt_(fmt);                               \
      constexpr size_t lhs = fmt_.count();                      \
      constexpr size_t rhs = VA_COUNT(__VA_ARGS__);             \
      static_assert(lhs == rhs, "size mismatch");               \
      static_assert(fmt_.error()+1 == 0, "misformatted");       \
      fmt_.scan_(is, ##__VA_ARGS__);                            \
    })

#define scan(...) fscan(std::cin, __VA_ARGS__)

__attribute__((constructor))
void ioinit() {
  std::ios_base::sync_with_stdio(false);
  std::cin.tie(nullptr);
  std::cerr.tie(nullptr);
  std::cout << std::fixed << std::setprecision(16);
}


#line 1 "~/git/library/utility/literals.cpp"



/**
 * @brief ユーザ定義リテラル
 * @author えびちゃん
 */

#line 11 "~/git/library/utility/literals.cpp"

constexpr intmax_t  operator ""_jd(unsigned long long n) { return n; }
constexpr uintmax_t operator ""_ju(unsigned long long n) { return n; }
constexpr size_t    operator ""_zu(unsigned long long n) { return n; }
constexpr ptrdiff_t operator ""_td(unsigned long long n) { return n; }

constexpr int8_t   operator ""_i8(unsigned long long n)  { return n; }
constexpr int16_t  operator ""_i16(unsigned long long n) { return n; }
constexpr int32_t  operator ""_i32(unsigned long long n) { return n; }
constexpr int64_t  operator ""_i64(unsigned long long n) { return n; }
constexpr uint8_t  operator ""_u8(unsigned long long n)  { return n; }
constexpr uint16_t operator ""_u16(unsigned long long n) { return n; }
constexpr uint32_t operator ""_u32(unsigned long long n) { return n; }
constexpr uint64_t operator ""_u64(unsigned long long n) { return n; }


#line 1 "~/git/library/utility/make/vector.cpp"



/**
 * @brief 多次元 vector の作成
 * @author えびちゃん
 */

#line 10 "~/git/library/utility/make/vector.cpp"
#include <type_traits>
#line 12 "~/git/library/utility/make/vector.cpp"

namespace detail {
  template <typename Tp, size_t Nb>
  auto make_vector(std::vector<size_t>& sizes, Tp const& x) {
    if constexpr (Nb == 1) {
      return std::vector(sizes[0], x);
    } else {
      size_t size = sizes[Nb-1];
      sizes.pop_back();
      return std::vector(size, make_vector<Tp, Nb-1>(sizes, x));
    }
  }
}  // detail::

template <typename Tp, size_t Nb>
auto make_vector(size_t const(&sizes)[Nb], Tp const& x = Tp()) {
  std::vector<size_t> s(Nb);
  for (size_t i = 0; i < Nb; ++i) s[i] = sizes[Nb-i-1];
  return detail::make_vector<Tp, Nb>(s, x);
}


#line 1 "~/git/library/utility/set_if.cpp"



/**
 * @brief 条件つき代入
 * @author えびちゃん
 */

#line 10 "~/git/library/utility/set_if.cpp"

template <typename Tp>
bool set_if_less(Tp& dst, Tp const& src) {
  if (src < dst) return (dst = src), true;
  return false;
}

template <typename Tp>
bool set_if_greater(Tp& dst, Tp const& src) {
  if (dst < src) return (dst = src), true;
  return false;
}


#line 1 "~/git/library/integer/bit.cpp"



/** 
 * @brief ビット演算
 * @author えびちゃん
 */

// XXX integral promotion 関連の注意をあまりしていません

#include <climits>
#include <type_traits>

template <typename Tp>
constexpr auto countl_zero(Tp n)
  -> typename std::enable_if<std::is_unsigned<Tp>::value, int>::type
{
  using value_type = typename std::make_unsigned<Tp>::type;
  int bits = (sizeof(value_type) * CHAR_BIT);
  if (n == 0) return bits;
  int res = 0;
  for (int i = bits / 2; i > 0; i /= 2) {
    value_type mask = ((static_cast<value_type>(1) << i) - 1) << i;
    if (n & mask) n >>= i;
    else res += i;
  }
  return res;
}
template <typename Tp>
constexpr auto countl_one(Tp n)
  -> typename std::enable_if<std::is_unsigned<Tp>::value, int>::type
{
  using value_type = typename std::make_unsigned<Tp>::type;
  return countl_zero(static_cast<value_type>(~n));
}

template <typename Tp>
constexpr auto countr_zero(Tp n)
  -> typename std::enable_if<std::is_unsigned<Tp>::value, int>::type
{
  using value_type = typename std::make_unsigned<Tp>::type;
  int bits = (sizeof(value_type) * CHAR_BIT);
  if (n == 0) return bits;
  int res = 0;
  for (int i = bits / 2; i > 0; i /= 2) {
    value_type mask = ((static_cast<value_type>(1) << i) - 1);
    if (!(n & mask)) res += i, n >>= i;
  }
  return res;
}
template <typename Tp>
constexpr auto countr_one(Tp n)
  -> typename std::enable_if<std::is_unsigned<Tp>::value, int>::type
{
  using value_type = typename std::make_unsigned<Tp>::type;
  return countr_zero(static_cast<value_type>(~n));
}

constexpr unsigned long long half_mask[] = {
  0x5555555555555555uLL, 0x3333333333333333uLL, 0x0F0F0F0F0F0F0F0FuLL,
  0x00FF00FF00FF00FFuLL, 0x0000FFFF0000FFFFuLL, 0x00000000FFFFFFFFuLL
};

template <typename Tp>
constexpr auto popcount(Tp n)
  -> typename std::enable_if<std::is_unsigned<Tp>::value, int>::type
{
  int bits = static_cast<int>((sizeof n) * CHAR_BIT);
  for (int i = 0, j = 1; j < bits; ++i, j *= 2) {
    if (j <= 8) n = (n & half_mask[i]) + ((n >> j) & half_mask[i]);
    else n += n >> j;
  }
  return n & 0xFF;
}

template <typename Tp>
constexpr auto parity(Tp n)
  -> typename std::enable_if<std::is_unsigned<Tp>::value, int>::type
{ return popcount(n) & 1; }


template <typename Tp>
int clz(Tp n) { return countl_zero(static_cast<typename std::make_unsigned<Tp>::type>(n)); }
template <typename Tp>
int ctz(Tp n) { return countr_zero(static_cast<typename std::make_unsigned<Tp>::type>(n)); }

template <typename Tp>
int ilog2(Tp n) {
  return (CHAR_BIT * sizeof(Tp) - 1) - clz(static_cast<typename std::make_unsigned<Tp>::type>(n));
}
template <typename Tp>
bool is_pow2(Tp n) { return (n > 0) && ((n & (n-1)) == 0); }
template <typename Tp>
Tp floor2(Tp n) { return is_pow2(n)? n: static_cast<Tp>(1) << ilog2(n); }
template <typename Tp>
Tp ceil2(Tp n) { return is_pow2(n)? n: static_cast<Tp>(2) << ilog2(n); }

template <typename Tp>
constexpr auto reverse(Tp n)
  -> typename std::enable_if<std::is_unsigned<Tp>::value, Tp>::type
{
  int bits = static_cast<int>((sizeof n) * CHAR_BIT);
  for (int i = 0, j = 1; j < bits; ++i, j *= 2) {
    n = ((n & half_mask[i]) << j) | ((n >> j) & half_mask[i]);
  }
  return n;
}


#line 18 "F.cpp"

int32_t f(std::map<int32_t, std::set<int32_t>> const& lf,
          std::map<int32_t, std::set<int32_t>> const& rg) {

  int32_t const inf = 1e8;
  int32_t res = inf;
  for (auto const& [kl, sl]: lf) {
    auto it = rg.find(kl);
    if (it == rg.end()) continue;
    auto const& sr = it->second;

    for (auto kx: sl) {
      auto it = sr.upper_bound(kx);
      if (it == sr.end()) continue;
      set_if_less(res, *it-kx);
    }
  }
  eprintln("{}", res);
  return res * 10;
}

int main() {
  size_t n;
  scan("{}", n);

  std::map<char, std::vector<std::pair<int32_t, int32_t>>> xy;

  for (size_t i = 0; i < n; ++i) {
    int32_t x, y;
    char u;
    scan("{} {} {}", x, y, u);
    xy[u].emplace_back(x, y);
  }

  int32_t const inf = 1e9;
  int32_t res = inf;

  {
    std::map<int32_t, std::set<int32_t>> lf;
    std::map<int32_t, std::set<int32_t>> rg;
    for (auto [x, y]: xy['R']) {
      lf[y-x].insert(x);
    }
    for (auto [x, y]: xy['D']) {
      rg[y-x].insert(x);
    }
    set_if_less(res, f(lf, rg));
  }
  {
    std::map<int32_t, std::set<int32_t>> lf;
    std::map<int32_t, std::set<int32_t>> rg;
    for (auto [x, y]: xy['U']) {
      lf[y-x].insert(x);
    }
    for (auto [x, y]: xy['L']) {
      rg[y-x].insert(x);
    }
    set_if_less(res, f(lf, rg));
  }

  {
    std::map<int32_t, std::set<int32_t>> lf;
    std::map<int32_t, std::set<int32_t>> rg;
    for (auto [x, y]: xy['R']) {
      lf[y+x].insert(x);
    }
    for (auto [x, y]: xy['U']) {
      rg[y+x].insert(x);
    }
    set_if_less(res, f(lf, rg));
  }
  {
    std::map<int32_t, std::set<int32_t>> lf;
    std::map<int32_t, std::set<int32_t>> rg;
    for (auto [x, y]: xy['D']) {
      lf[y+x].insert(x);
    }
    for (auto [x, y]: xy['L']) {
      rg[y+x].insert(x);
    }
    set_if_less(res, f(lf, rg));
  }


  {
    std::map<int32_t, std::set<int32_t>> lf;
    std::map<int32_t, std::set<int32_t>> rg;
    for (auto [x, y]: xy['R']) {
      lf[y].insert(x);
    }
    for (auto [x, y]: xy['L']) {
      rg[y].insert(x);
    }
    auto tmp = f(lf, rg);
    if (tmp < inf) set_if_less(res, tmp / 2);
  }
  {
    std::map<int32_t, std::set<int32_t>> lf;
    std::map<int32_t, std::set<int32_t>> rg;
    for (auto [x, y]: xy['U']) {
      lf[x].insert(y);
    }
    for (auto [x, y]: xy['D']) {
      rg[x].insert(y);
    }
    auto tmp = f(lf, rg);
    if (tmp < inf) set_if_less(res, tmp / 2);
    // set_if_less(res, f(lf, rg) / 2);
  }

  if (res == inf) return println("SAFE"), 0;
  println("{}", res);
}


Measured memory_bytes: 32540