#include<bits/stdc++.h>
#define rep(i,a,b) for(int i=int(a);i<int(b);++i)
using namespace std;
typedef long long ll;
int INF = (1LL << 30) - 1;
int MOD = 1e9+7;
main(){
    string S = "abcdefghi";
    int N;
    cin >> N;
    rep(i,0,N-1){
        cout << "a" + S + "a" << endl;
        next_permutation(S.begin(), S.end());
    }
    cout << "an" << endl;
}