#include<bits/stdc++.h>
using namespace std;
//#include<ext/pb_ds/assoc_container.hpp>
//#include<ext/pb_ds/tree_policy.hpp>
//
//    #pragma GCC optimize("unroll-loops")
//    #pragma GCC optimize("Ofast")
//    #pragma GCC optimize("-O3")
//    #pragma GCC optimize("no-stack-protector")
//    #pragma GCC optimize("fast-math")
#pragma GCC optimize("Ofast")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx")
//#define LOCAL
#define sim template < class c
#define ris return * this
#define dor > debug & operator <<
#define eni(x) sim > typename \
  enable_if<sizeof dud<c>(0) x 1, debug&>::type operator<<(c i) {
sim > struct rge { c b, e; };
sim > rge<c> range(c i, c j) { return rge<c>{i, j}; }
sim > auto dud(c* x) -> decltype(cerr << *x, 0);
sim > char dud(...);
struct debug {
#ifndef LOCAL
~debug() { cerr << endl; }
eni(!=) cerr << boolalpha << i; ris; }
eni(==) ris << range(begin(i), end(i)); }
sim, class b dor(pair < b, c > d) {
  ris << "(" << d.first << ", " << d.second << ")";
}
sim dor(rge<c> d) {
  *this << "[";
  for (auto it = d.b; it != d.e; ++it)
	*this << ", " + 2 * (it == d.b) << *it;
  ris << "]";
}
#else
sim dor(const c&) { ris; }
#endif
};
#define imie(...) " [" << #__VA_ARGS__ ": " << (__VA_ARGS__) << "] "
#define fi first
#define f first
#define se second
#define s second
#define vi_a vector<int>a;
#define p_b push_back
////////////////////////////////???????????????CHECK THIS OUT???????????????//////////////////////////////
#define ll long long
typedef unsigned long long ull;
////////////////////////////////???????????????CHECK THIS OUT???????????????//////////////////////////////
#define ld long double
#define pll pair<ll,ll>
#define pii pair<int,int>
#define m_p make_pair
#define fast_io cin.tie(0);cout.tie(0);ios_base::sync_with_stdio(0);
#define all(x) x.begin(),x.end()
#define getfiles    ifstream cin("input.txt");ofstream cout("output.txt");
#define pw(x) (1ll << x)
#define sz(x) (int)x.size()
#define endl "\n"
#define rall(x) x.rbegin(),x.rend()
#define len(a) (ll)a.size()
#define rep(x,l,r) for(ll x=l;x<r;x++)

//using namespace __gnu_pbds;
ld eps = (ld)1 / 1e6;
const ld pi=3.14159265359;
ll inf = 1e18,mod1=1e9+7;
ll sqr(ll a) { return a * a; }
ll qb(ll a) { return a * a * a; }
ll gcd(ll a, ll b) { return !a ? b : gcd(b % a, a); }
ll binpow(ll a, ll b, ll mod) { return b ? (b % 2 ? (a * (sqr(binpow(a, b / 2, mod)) % mod)) % mod : sqr(binpow(a, b / 2, mod)) % mod) : 1; }
ll binmult(ll a, ll b, ll mod) { return b ? (b % 2 ? (2 * binmult(a, b / 2, mod) + a) % mod : (2 * binmult(a, b / 2, mod)) % mod) : 0; }
/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
const ll R=1e4;
const ll tx[4]={0,0,-1,1};
const ll ty[4]={-1,1,0,0};
const char rev_to[4]={'E','W','N','S'};
const int N=2e6+1;
const int M=1e9+7;
const int Y=1;
const int X=0;
//typedef tree<ll,null_type,less<ll>,rb_tree_tag,tree_order_statistics_node_update> st;
auto rnd=bind(uniform_int_distribution<ll>(1,125),mt19937(time(0)));
void bad(){
    cout<<-1;
    exit(0);
}
int n;
vector<pii>l,r,d,u;
int x,y;char c;
signed main()
{
    fast_io;
    cin>>n;
    for(int i=0;i<n;i++){
        cin>>x>>y>>c;x*=10;y*=10;
        if(c=='U') u.p_b({x,y});
        if(c=='D') d.p_b({x,y});
        if(c=='L') l.p_b({x,y});
        if(c=='R') r.p_b({x,y});
    }
    sort(all(l));sort(all(d));sort(all(r));sort(all(u));
    /// LR
    map<int,set<int>>mp;
    int ans=2e9;
    for(auto &z : r) mp[z.s].insert(z.f);
    for(auto &z : l){
        auto it=mp[z.s].upper_bound({z.f});
        if(it!=mp[z.s].begin()){
            --it;
            ans=min(ans,abs(z.f-*it)/2);
        }
    }mp.clear();
    ///UD
    for(auto &z : u) mp[z.f].insert(z.s);
    for(auto &z : d){
        auto it=mp[z.f].upper_bound({z.s});
        if(it!=mp[z.f].begin()){
            --it;
            ans=min(ans,abs(z.s-*it)/2);
        }
    }mp.clear();
    /// RD
    for(auto &z : d) mp[z.s-z.f].insert(z.f);
    for(auto &z : r){
        auto it=mp[z.s-z.f].lower_bound({z.f});
        if(it!=mp[z.s-z.f].end()){
            ans=min(ans,(abs(z.f-*it)));
        }
    }mp.clear();
    /// LD
    for(auto &z : d) mp[z.f+z.s].insert(z.f);
    for(auto &z : l){
        auto it=mp[z.f+z.s].upper_bound({z.f});
        if(it!=mp[z.f+z.s].begin()){
            it--;   ans=min(ans,(abs(z.f-*it)));
        }
    }mp.clear();
    ///RU
    for(auto &z : u) mp[z.f+z.s].insert(z.f);
    for(auto &z : r){
        auto it=mp[z.s+z.f].lower_bound({z.f});
        if(it!=mp[z.s+z.f].end()){
            ans=min(ans,(abs(z.f-*it)));
        }
    }mp.clear();
    /// LU
    for(auto &z : u) mp[z.s-z.f].insert(z.f);
    for(auto &z : l){
        auto it=mp[z.s-z.f].upper_bound({z.f});
        if(it!=mp[z.s-z.f].begin()){
            it--; ans=min(ans,(abs(z.f-*it)));
        }
    }mp.clear();
    if(ans==2e9) cout<<"SAFE";
    else cout<<ans;
    return 0;
}
/*
0 0 0
2 1 3
3 2 7
1 3 8
1 4 2
3 5 3

/
*/


Measured memory_bytes: 32528