#include #include #include #include #include #include #include #include #include #define repd(i,a,b) for (int i=(a);i<(b);i++) #define rep(i,n) repd(i,0,n) typedef long long ll; using namespace std; int inputValue(){ int a; cin >> a; return a; }; void inputArray(int * p, int a){ rep(i, a){ cin >> p[i]; } }; void inputVector(vector * p, int a){ rep(i, a){ int input; cin >> input; p -> push_back(input); } } template void output(T a, int precision) { if(precision > 0){ cout << setprecision(precision) << a << "\n"; } else{ cout << a << "\n"; } } int main(int argc, const char * argv[]) { // source code int N = inputValue(); vector str(N); rep(i, N){ cin >> str[i]; } string b, s; s = "xnbmgr"; b = "iaaeuu"; sort(b.begin(), b.end()); sort(s.begin(), s.end()); do{ do{ string m; rep(i, 6){ if (s[i] != 'x') { m.push_back(s[i]); } m.push_back(b[i]); } auto it = find(str.begin(), str.end(), m); if (it == str.end()) { output(m, 0); return 0; } } while(next_permutation(b.begin(), b.end())); }while(next_permutation(s.begin(), s.end())); output("NO", 0); return 0; }