#include <bits/stdc++.h>
using namespace std;
struct fast_ios { fast_ios(){ cin.tie(0); ios::sync_with_stdio(false); cout << fixed << setprecision(20); }; } fast_ios_;
#define FOR(i, begin, end) for(int i=(begin);i<(end);i++)
#define REP(i, n) FOR(i,0,n)
#define IFOR(i, begin, end) for(int i=(end)-1;i>=(begin);i--)
#define IREP(i, n) IFOR(i,0,n)
#define Sort(v) sort(v.begin(), v.end())
#define Reverse(v) reverse(v.begin(), v.end())
#define all(v) v.begin(),v.end()
#define SZ(v) ((int)v.size())
#define Lower_bound(v, x) distance(v.begin(), lower_bound(v.begin(), v.end(), x))
#define Upper_bound(v, x) distance(v.begin(), upper_bound(v.begin(), v.end(), x))
#define chmax(a, b) a = max(a, b)
#define chmin(a, b) a = min(a, b)
#define bit(n) (1LL<<(n))
#define debug(x) cout << #x << "=" << x << endl;
#define vdebug(v) { cout << #v << "=" << endl; REP(i_debug, v.size()){ cout << v[i_debug] << ","; } cout << endl; }
#define mdebug(m) { cout << #m << "=" << endl; REP(i_debug, m.size()){ REP(j_debug, m[i_debug].size()){ cout << m[i_debug][j_debug] << ","; } cout << endl;} }
#define pb push_back
#define fi first
#define se second
#define int long long
#define INF 1000000000000000000
template<typename T> istream &operator>>(istream &is, vector<T> &v){ for (auto &x : v) is >> x; return is; }
template<typename T> ostream &operator<<(ostream &os, vector<T> &v){ for(int i = 0; i < v.size(); i++) { cout << v[i]; if(i != v.size() - 1) cout << endl; }; return os; }
template<typename T1, typename T2> ostream &operator<<(ostream &os, pair<T1, T2> p){ cout << '(' << p.first << ',' << p.second << ')'; return os; }
template<typename T> void Out(T x) { cout << x << endl; }
template<typename T1, typename T2> void chOut(bool f, T1 y, T2 n) { if(f) Out(y); else Out(n); }

using vec = vector<int>;
using mat = vector<vec>;
using Pii = pair<int, int>;
using v_bool = vector<bool>;
using v_Pii = vector<Pii>;

//int dx[4] = {1,0,-1,0};
//int dy[4] = {0,1,0,-1};
//char d[4] = {'D','R','U','L'};

const int mod = 1000000007;
//const int mod = 998244353;



signed main(){

    int N; cin >> N;
    vec x(N), y(N);
    string u(N, '.');
    REP(i, N) cin >> x[i] >> y[i] >> u[i];

    int ans = INF;

    const int S = 400000;
    vector<v_Pii> ls(S + 1);
    string check = "RDUL";
    REP(i, N){
        int t = x[i] - y[i] + S / 2;
        ls[t].pb(Pii(x[i], i));
    }
    REP(k, S + 1) if(SZ(ls[k])){
        Sort(ls[k]);
        vec last(2, -INF);
        for(Pii q: ls[k]){
            int t = q.fi;
            char c = u[q.se];
            if(c == check[0]) last[0] = t;
            else if(c == check[1] && last[0] > -INF) chmin(ans, (t - last[0]) * 10);
            else if(c == check[2]) last[1] = t;
            else if(c == check[3] && last[1] > -INF) chmin(ans, (t - last[1]) * 10);
        }
    }

    ls = vector<v_Pii>(S + 1);
    check = "RUDL";
    REP(i, N){
        int t = x[i] + y[i];
        ls[t].pb(Pii(x[i], i));
    }
    REP(k, S + 1) if(SZ(ls[k])){
        Sort(ls[k]);
        vec last(2, -INF);
        for(Pii q: ls[k]){
            int t = q.fi;
            char c = u[q.se];
            if(c == check[0]) last[0] = t;
            else if(c == check[1] && last[0] > -INF) chmin(ans, (t - last[0]) * 10);
            else if(c == check[2]) last[1] = t;
            else if(c == check[3] && last[1] > -INF) chmin(ans, (t - last[1]) * 10);
        }
    }

    ls = vector<v_Pii>(S + 1);
    check = "UD@@";
    REP(i, N){
        int t = x[i];
        ls[t].pb(Pii(y[i], i));
    }
    REP(k, S + 1) if(SZ(ls[k])){
        Sort(ls[k]);
        vec last(2, -INF);
        for(Pii q: ls[k]){
            int t = q.fi;
            char c = u[q.se];
            if(c == check[0]) last[0] = t;
            else if(c == check[1] && last[0] > -INF) chmin(ans, (t - last[0]) * 5);
            else if(c == check[2]) last[1] = t;
            else if(c == check[3] && last[1] > -INF) chmin(ans, (t - last[1]) * 5);
        }
    }

    ls = vector<v_Pii>(S + 1);
    check = "RL@@";
    REP(i, N){
        int t = y[i];
        ls[t].pb(Pii(x[i], i));
    }
    REP(k, S + 1) if(SZ(ls[k])){
        Sort(ls[k]);
        vec last(2, -INF);
        for(Pii q: ls[k]){
            int t = q.fi;
            char c = u[q.se];
            if(c == check[0]) last[0] = t;
            else if(c == check[1] && last[0] > -INF) chmin(ans, (t - last[0]) * 5);
            else if(c == check[2]) last[1] = t;
            else if(c == check[3] && last[1] > -INF) chmin(ans, (t - last[1]) * 5);
        }
    }

    chOut(ans < INF, ans, "SAFE");

    return 0;
}


Measured memory_bytes: 31660