#include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
using namespace std;
#define int         long long
#define mod         1000000007
#define FAST        ios::sync_with_stdio(0),cin.tie(0),cout.tie(0);
#define f(i,n)      for(int i=0;i<n;i++)
#define fp(i,k,n)   for(int i=k;i<=n;i++)
#define fr(i,k,n)   for(int i=k;i>=n;i--)
#define pb          push_back
#define pii         pair<int,int>
#define vi          vector<int>
#define vii         vector<pii>
#define dbg(x)      cout << (#x) << " is " << (x) << '\n' 
#define F           first
#define S           second
#define sz(x)       (int)(x).size()
#define lb          lower_bound
#define ub          upper_bound
#define mems(x)     memset(x,0,sizeof(x))
#define all(a)      a.begin(),a.end()
typedef tree<int,null_type,less_equal<int>,rb_tree_tag,tree_order_statistics_node_update>ordered_set;
 
/*---------------------------------------------------------------------------------------------------*/ 

void solve()
{
 int n;
 cin >> n;
 map<string,int> mp,mp1;
 int ok=0;
 string res;
 res="";
 f(i,n)
 {
   string x;
   cin >> x;
   if(x[0]=='!')
   {
     if((int)x.length()==1)
      continue;
     string y=x.substr(1,(int)x.length()-1);
     mp[y]++;
     if(mp[y]>=1 && mp1[y]>=1)
      {res=y;ok=1;}
   }
   else
   {
     mp1[x]++;
     if(mp[x]>=1 && mp1[x]>=1)
      {
        res=x;ok=1;
      }
   }
 }
 if(ok)
  cout << res << '\n';
 else
  cout << "satisfiable\n";
 return;       
}

signed main()
{
  // freopen("input.txt","r",stdin);
  // freopen("output.txt","w",stdout);
  FAST
  int T=1;
  // cin >> T;
  while(T--)
  {
    solve();
  }
  return 0;
}
// Sakhiya07 - Yagnik Sakhiya
  
#include <bits/stdc++.h>
using namespace std;

#define ll long long
#define pb push_back
#define all(x) x.begin(),x.end()

#define pll pair<ll,ll>
#define ff first
#define ss second

#define MOD 1000000007

const int N = 100005; 

void solve() 
{
    ll n;
    cin >> n;
    map<ll,ll> y;
    bool chk = 1;
    for(ll i=0,x;i<n;i++) {
        cin >> x;
        y[x]++;
    }
    for(ll i = 1 ; i <= n ; i++) {
        if(y[i] != 1)  chk = 0;
    } 
    if(chk)  cout <<"Yes\n";
    else     cout << "No\n";
}

int main() 
{
    ios_base::sync_with_stdio(false);
    cin.tie(0), cout.tie(0);

    int t = 1;

    for(int i = 1; i < t + 1; i++) {
        solve();
    }
    
}