#include <iostream>
#include <map>
#include <vector>
#include <utility>
#include <algorithm>
using namespace std;
typedef pair <int, string> psi;
#define x first
#define y second
#define mp make_pair
map <string, bool> m;
map <string, int> dth;
map <string, map <psi, bool, greater <psi> > > svi;
int n;
int main(){
ios_base::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
cin >> n;
for(int i = 0 ; i < n ; ++i){
string s;
cin >> s;
char poc;
cin >> poc;
map <string, bool> ovaj;
while(1){
string x;
cin >> x;
if(x == ";")
break;
ovaj[x] = 1;
}
if(m.find(s) != m.end()){
cout << "greska" << endl;
continue;
}
bool p = 1;
int sad = 0;
map <psi, bool, greater <psi> > taj;
for(map <string, bool>::iterator j = ovaj.begin() ; j != ovaj.end() ; ++j){
string x = j->x;
if(m.find(x) == m.end()){
p = 0;
break;
}
sad = max(sad, dth[x] + 1);
taj[mp(dth[x], x)] = 1;
}
/*
for(map <psi, bool>::iterator j = taj.begin() ; j != taj.end() ; ++j){
psi o = j->x;
cout << o.y << " : " << o.x << endl;
}
*/
if(!p){
cout << "greska" << endl;
continue;
}
map <string, bool> gornji;
for(map <psi, bool>::iterator j = taj.begin() ; j != taj.end() ; ++j){
string x = (j->x).y;
if(gornji.find(x) != gornji.end())
continue;
for(map <psi, bool>::iterator v = svi[x].begin() ; v != svi[x].end() ; ++v){
string y = (v->x).y;
if(gornji.find(y) != gornji.end()){
p = 0;
break;
}
gornji[y] = 1;
}
if(!p)
break;
}
if(!p){
cout << "greska" << endl;
continue;
}
cout << "ok" << endl;
m[s] = 1;
dth[s] = sad;
gornji.clear();
for(map <psi, bool>::iterator j = taj.begin() ; j != taj.end() ; ++j){
string x = (j->x).y;
if(svi[s].find(mp(dth[x], x)) != svi[s].end())
continue;
svi[s][mp(dth[x], x)] = 1;
for(map <psi, bool>::iterator v = svi[x].begin() ; v != svi[x].end() ; ++v){
string y = (v->x).y;
svi[s][mp(dth[y], y)] = 1;
}
}
//cout << endl << endl;
}
return 0;
}
