#include <iostream>
#include <vector>
#include <string>
#include <unordered_set>

int main()
{
	int N;
	std::cin >> N;
	std::vector<std::string>S(N);
	for (std::string& s : S)
		std::cin >> s;
	std::unordered_set<std::string>h(S.begin(), S.end());
	for (std::string &s:S)
		if (h.count('!' + s))
		{
			std::cout << s << '\n';
			return 0;
		}
	std::cout << "satisfiable" << '\n';
}
#include <bits/stdc++.h>
using namespace std;
//#define FOR_CODEFORCES
//#define MOD 998244353LL

#if 1 //テンプレ折り畳み//テンプレ折り畳み//テンプレ折り畳み

#ifdef _DEBUG
#define debug() if(true)
#define dout cout
#define dvout(v) __vout(v)
#define dvvout(v) __vvout(v)
#else
#define debug() if (false)
#define dout if (false)cout
#define dvout(v) if (false)vout(v)
#define dvout(v) if(false)__vout(v)
#define dvvout(v) if(false)__vvout(v)
#endif

typedef long long ll;
typedef unsigned long long ull;

#define rep(i, n) for(int i=0, i##_len=(n); i<i##_len; ++i)//rep
#define repi(i, n1, n) for(int i=n1, i##_len=(n); i<i##_len; ++i)//rep
#define reps(i, n) for(int i=1, i##_len=(n); i<=i##_len; ++i)//自然数rep
#define rrep(i, n) for(int i=((int)(n)-1); i>=0; --i)
#define rreps(i, n) for(int i=((int)(n)); i>0; --i)

#define _Yes {cout<<"Yes"<<endl; return;}//出力
#define _No {cout<<"No"<<endl;return;}
#define _ans {cout<<ans<<endl;return;}
#define _endout(s) {cout<<(s)<<endl;return;}

#define vec(v, n) vector<int> v(n, 0);//配列
#define vecll(v, n) vector<ll> v(n, 0);
#define vecvec(v, n, m) vector<vector<int>> v(n, vector<int>(m));
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<ll> vll;
#define vin(v) for (auto &i : (v)) cin >> i; //配列入力
#define vvin(v) for(auto&i:(v))for(auto&j:i)cin>>j;
#define __vout(v) for(auto&i:(v)){cout<<i<<' ';}cout<<"\n";
#define __vvout(v) for(auto&i:(v)){for(auto&j:i){cout<<j<<' ';}cout<<"\n";}cout<<"\n";

#ifndef MOD
#define MOD 1000000007LL//mod用定数 (ll)(1e9+7)
#endif
#define mod(n) ( ((ll)n) % MOD)
#define modp(n, p) ( ((ll)n) % (ll)(p))
#define modx(A,B) mod(mod(A)*mod(B))
template<class T>bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }
template<class T>bool chmin(T &a, const T &b) { if (a>b) { a=b; return 1; } return 0; }

#define next asdnext
#define prev asdprev
#define y0 y3487465
#define y1 y8687969
#define j0 j1347829
#define j1 j234892
#define SZ(x) ((int)(x).size())
#define all(x) (x).begin(), (x).end()
#define _n "\n"
#define _n2 "\n\n"
#define _t "\t"

void test();

#endif //テンプレ折り畳み

//	LLONG_MAX 9.2*1e18	9223372036854775807LL = (2^63)-1
//	INT_MAX 2.1*1e9 2147483647 = (2^31)-1
//	O(1e8) 1.2sec

void Main()
{
	int N;
	cin>>N;
	vector<string> S(N);
	map<string, int> m;
	rep(i,N){
		cin>>S[i];
		m[S[i]]=1;
	}

	rep(i,N){
		if(m.count("!"+S[i]))_endout(S[i])
	}

	_endout("satisfiable");
}

void test(){
}
int main(){
	cin.tie(nullptr);
	ios_base::sync_with_stdio(false);
	cout << std::fixed << std::setprecision(20);
#ifdef FOR_CODEFORCES
	int t = 0;
	cin >> t;
	rep(i, t) Main();
#else
	Main();
#endif
	return 0;
}
