#pragma GCC optimize("O3") #pragma GCC target("avx") #include "bits/stdc++.h" using namespace std; #define int long long #define REP(i, n) for (int i = 0; i < (n); i++) #define FOR(i, a, b) for (int i = (a); i < (b); i++) #define FORR(i, a, b) for (int i = (b - 1); i >= (a); i--) #define ALL(a) begin(a), end(a) #define let const auto int scan() { int result = 0; while (true) { auto k = getchar_unlocked(); if (k < '0' || k > '9') break; result = 10 * result + k - '0'; } return result; } string S = "aabegimnruu"; auto used = unordered_set(); #define is_consonant(c) \ (c == 'n' || c == 'b' || c == 'm' || c == 'g' || c == 'r') bool impl() { if (is_consonant(S[10])) return false; REP(i, 11) { if (is_consonant(S[i]) && is_consonant(S[i - 1])) return false; } if (used.find(S) == used.end()) { printf("%s\n", S.c_str()); return true; } return false; } char cache[100] = {}; signed main() { let n = scan(); if (n == 129600) { // 最大値は計算で出せる printf("NO\n"); return 0; } // string cache = "inabameguru"; REP(_, n) { fgets(cache, 11, stdin); // REP(i, 11) cache[i] = getchar_unlocked(); used.insert(cache); // getchar_unlocked(); }; do if (impl()) return 0; while (next_permutation(ALL(S))); }