#include<bits/stdc++.h>
using namespace std;
int main()
{
	int n;
	cin>>n;
	string s[n];
	set<string> val;
	for(int i=0;i<n;i++)
	{cin>>s[i];val.insert(s[i]);}
	for(int i=0;i<n;i++)
	{
		//if(s[i][0]!='!')	continue;
		if(val.count('!'+s[i]))
		{
			cout<<s[i];
			exit(0);
		}
	}
	cout<<"satisfiable";
}
#include <algorithm>
#include <bitset>
#include <cassert>
#include <cctype>
#include <cfloat>
#include <climits>
#include <cmath>
#include <cstdio>
#include <deque>
#include <iomanip>
#include <iostream>
#include <list>
#include <map>
#include <queue>
#include <random>
#include <set>
#include <stack>
#include <string>
#include <unordered_set>
#include <vector>
using namespace std;
typedef long double ld;
typedef long long int ll;
typedef unsigned long long int ull;
typedef vector<int> vi;
typedef vector<char> vc;
typedef vector<bool> vb;
typedef vector<double> vd;
typedef vector<string> vs;
typedef vector<ll> vll;
typedef vector<pair<int, int>> vpii;
typedef vector<pair<ll, ll>> vpll;
typedef vector<vi> vvi;
typedef vector<vvi> vvvi;
typedef vector<vc> vvc;
typedef vector<vs> vvs;
typedef vector<vll> vvll;
typedef map<int, int> mii;
typedef set<int> si;
#define rep(i, n) for (ll i = 0; i < (n); ++i)
#define rrep(i, n) for (int i = 1; i <= (n); ++i)
#define irep(it, stl) for (auto it = stl.begin(); it != stl.end(); it++)
#define drep(i, n) for (int i = (n)-1; i >= 0; --i)
#define fin(ans) cout << (ans) << '\n'
#define STLL(s) strtoll(s.c_str(), NULL, 10)
#define mp(p, q) make_pair(p, q)
#define pb(n) push_back(n)
#define all(a) a.begin(), a.end()
#define Sort(a) sort(a.begin(), a.end())
#define Rort(a) sort(a.rbegin(), a.rend())
#define fi first
#define se second
// #include <atcoder/all>
// using namespace atcoder;
constexpr int dx[8] = {1, 0, -1, 0, 1, -1, -1, 1};
constexpr int dy[8] = {0, 1, 0, -1, 1, 1, -1, -1};
template <class T, class U>
inline bool chmax(T& a, U b) {
    if (a < b) {
        a = b;
        return 1;
    }
    return 0;
}
template <class T, class U>
inline bool chmin(T& a, U b) {
    if (a > b) {
        a = b;
        return 1;
    }
    return 0;
}
template <class T>
inline void dump(T& v) {
    irep(i, v) { cout << (*i) << ((i == --v.end()) ? '\n' : ' '); }
}
template <class T, class U>
inline void dump(map<T, U>& v) {
    irep(i, v) { cout << i->first << " " << i->second << '\n'; }
}
template <class T, class U>
inline void dump(pair<T, U>& p) {
    cout << p.first << " " << p.second << '\n';
}
string getline() {
    string s;
    fflush(stdin);
    getline(cin, s);
    return s;
}
inline void yn(const bool b) { b ? fin("yes") : fin("no"); }
inline void Yn(const bool b) { b ? fin("Yes") : fin("No"); }
inline void YN(const bool b) { b ? fin("YES") : fin("NO"); }
template <typename Head, typename Value>
auto vectors(const Head& head, const Value& v) {
    return vector<Value>(head, v);
}
template <typename Head, typename... Tail>
auto vectors(Head x, Tail... tail) {
    auto inner = vectors(tail...);
    return vector<decltype(inner)>(x, inner);
}
const int INF = INT_MAX;
constexpr ll LLINF = 1LL << 61;
constexpr ll MOD = 1000000007;  // 998244353;
constexpr ld EPS = 1e-11;

/* --------------------   ここまでテンプレ   -------------------- */

int main() {
    map<string, int> m;
    int n;
    cin>>n;
    rep(i,n){
        string s;
        cin>>s;
        string t=s;
        int bi=0;
        if(s[0]=='!')bi=1;
        if(t[0]=='!')t=t.substr(1);
        m[t]|=(1<<bi);
    }
    irep(i,m){
        if(i->second==3){
            cout<<i->first<<endl;
            return 0;
        }
    }
    fin("satisfiable");
}
