#include <bits/stdc++.h>
#ifdef LOCAL_DEBUG
#define DEBUG 1
#define CERR if(DEBUG) cerr
#define MACRO(_1,_2,_3,_4,_5,_6,_7,_8,_9,_10,NAME,...) NAME
#define pr(...) CERR<<MACRO(__VA_ARGS__,pr10,pr9,pr8,pr7,pr6,pr5,pr4,pr3,pr2,pr1)(__VA_ARGS__)<<endl
#define pr1(a) (#a)<<"="<<(a)<<" "
#define pr2(a,b) pr1(a)<<pr1(b)
#define pr3(a,b,c) pr1(a)<<pr2(b,c)
#define pr4(a,b,c,d) pr1(a)<<pr3(b,c,d)
#define pr5(a,b,c,d,e) pr1(a)<<pr4(b,c,d,e)
#define pr6(a,b,c,d,e,f) pr1(a)<<pr5(b,c,d,e,f)
#define pr7(a,b,c,d,e,f,g) pr1(a)<<pr6(b,c,d,e,f,g)
#define pr8(a,b,c,d,e,f,g,h) pr1(a)<<pr7(b,c,d,e,f,g,h)
#define pr9(a,b,c,d,e,f,g,h,i) pr1(a)<<pr8(b,c,d,e,f,g,h,i)
#define pr10(a,b,c,d,e,f,g,h,i,j) pr1(a)<<pr9(b,c,d,e,f,g,h,i,j)
#define prArr(a){CERR<<(#a)<<"={";int i=0;for(auto t:(a))CERR<<(i++?", ":"")<<t;CERR<<"}"<<endl;}
#else
#define DEBUG 0
#define pr(...)
#define prArr(a)
#endif
using namespace std;
using Int = long long;
using _int = int;
using ll = long long;
using Double = long double;
const Int INF = (1LL<<55)+1e9; // ~ 1.15 * 1e18
const Int mod = (1e9)+7;
const Double EPS = 1e-8;
const Double PI = 6.0 * asin((Double)0.5);
using P = pair<Int,Int>;
template<class T> T Max(T &a,T b){return a=max(a,b);}
template<class T> T Min(T &a,T b){return a=min(a,b);}
template<class T1, class T2> ostream& operator<<(ostream& o,pair<T1,T2> p){return o<<"("<<p.first<<","<<p.second<<")";}
template<class T1, class T2, class T3> ostream& operator<<(ostream& o,tuple<T1,T2,T3> t){return o<<"("<<get<0>(t)<<","<<get<1>(t)<<","<<get<2>(t)<<")";}
template<class T1, class T2> istream& operator>>(istream& i,pair<T1,T2> &p){return i>>p.first>>p.second;}
template<class T> ostream& operator<<(ostream& o,vector<T> a){Int i=0;for(T t:a)o<<(i++?" ":"")<<t;return o;}
template<class T> istream& operator>>(istream& i,vector<T> &a){for(T &t:a)i>>t;return i;}
//INSERT ABOVE HERE
using T = tuple<Int, Int, char>;
Int N;
vector<T> A;
const Int V = 200010;

Int solve1(){
  vector<vector<Int> > U(V), R(V), D(V), L(V);
  for(Int i=0;i<N;i++){
    Int x, y;
    char ch;
    tie(x, y, ch) = A[i];
    if(ch == 'U') U[x].push_back(y);
    if(ch == 'D') D[x].push_back(y);
    if(ch == 'L') L[y].push_back(x);
    if(ch == 'R') R[y].push_back(x);
  }

  for(Int i=0;i<V;i++){
    sort(U[i].begin(), U[i].end());
    sort(R[i].begin(), R[i].end());
    sort(L[i].begin(), L[i].end());
    sort(D[i].begin(), D[i].end());
  }

  Int res = INF;
  for(Int i=0;i<V;i++){
    for(Int y:U[i]){
      auto it = lower_bound(D[i].begin(), D[i].end(), y);
      if(it == D[i].end()) continue;
      Int yy = *it;
      Min(res, (yy - y));
    }

    for(Int x:R[i]){
      auto it = lower_bound(L[i].begin(), L[i].end(), x);
      if(it == L[i].end()) continue;
      Int xx = *it;
      Min(res, (xx - x));
    }
  }
  return res;
}

Int solve2_1(){
  vector<vector<Int> > U(V * 3), R(V * 3), D(V * 3), L(V * 3);
  Int ofset = V;
  for(Int i=0;i<N;i++){
    Int u, v;
    char ch;
    tie(u, v, ch) = A[i];
    Int x = u + v + ofset;
    Int y = u - v + ofset;
    assert(x >= 0 && x < V * 3);
    assert(y >= 0 && y < V * 3);
    if(ch == 'U') U[y].push_back(x);
    if(ch == 'D') D[y].push_back(x);
    if(ch == 'L') L[y].push_back(x);
    if(ch == 'R') R[y].push_back(x);
  }

  for(Int i=0;i<3 * V;i++){
    sort(U[i].begin(), U[i].end());
    sort(R[i].begin(), R[i].end());
    sort(L[i].begin(), L[i].end());
    sort(D[i].begin(), D[i].end());
  }

  Int res = INF;
  for(Int i=0;i<V * 3;i++){

    for(Int y:U[i]){
      auto it = lower_bound(L[i].begin(), L[i].end(), y);
      if(it == L[i].end()) continue;
      Int yy = *it;
      assert((yy - y) % 2 == 0);
      Min(res, (yy - y));
    }

    /*
    for(Int y:U[i]){
    auto it = lower_bound(R[i].begin(), R[i].end(), y);
    if(it == R[i].end()) continue;
    Int yy = *it;
    assert((yy - y) % 2 == 0);
    Min(res, (yy - y) / 2);
    }
    */

  }
  return res;
}
Int solve2_2(){
  auto tmp = A;
  Int VV = 200005;
  for(Int i=0;i<N;i++){
    Int x, y;
    char ch;
    tie(x, y, ch) = A[i];
    x = VV - x;
    if(ch == 'L') ch = 'R';
    else if(ch == 'R') ch = 'L';
    A[i] = T(x, y, ch);
  }
  auto res =  solve2_1();
  A = tmp;
  return res;
}
Int solve2(){
  Int a = solve2_1();
  Int b = solve2_2();
  return min(a, b);
}

Int solve3(){
  auto tmp = A;
  Int VV = 200005;
  for(Int i=0;i<N;i++){
    Int x, y;
    char ch;
    tie(x, y, ch) = A[i];
    y = VV - y;
    if(ch == 'U') ch = 'D';
    else if(ch == 'D') ch = 'U';
    A[i] = T(x, y, ch);
  }
  Int res = solve2();
  A = tmp;
  return res;
}

signed main(){
  srand((unsigned)time(NULL));
  cin.tie(0);
  ios_base::sync_with_stdio(0);
  cout << fixed << setprecision(12);

  cin>>N;
  for(Int i=0;i<N;i++){
    Int x, y;
    char ch;
    cin>>x>>y>>ch;
    A.push_back(T(x, y, ch));
  }

  Int a = solve1();
  Int b = solve2();
  Int c = solve3();
  if(a == INF && b == INF && c == INF){
    cout<<"SAFE"<<endl;
    return 0;
  }
  a *= 10/2;
  b *= 10/2;
  c *= 10/2;
  Int ans = min({a, b, c});
  cout<<ans<<endl;
  return 0;
}


Measured memory_bytes: 88684