#include <bits/stdc++.h>
using namespace std;

int main() {
    int N;
    cin >> N;
    set<string> used;
    for (int i = 0; i < N; i++) {
        string s;
        cin >> s;
        used.insert(s);
    }
    string sabbat_of_the_witch = "inabameguru";
    do {
        if (used.count(sabbat_of_the_witch) == 0) {
            cout << sabbat_of_the_witch << endl;
            return 0;
        }
    } while (next_permutation(sabbat_of_the_witch.begin(), sabbat_of_the_witch.end()));
    cout << "NO" << endl;
}