#include <bits/stdc++.h>
#define rep(i,n) for(int i = 0; i < (n); i++)
using namespace std;
typedef long long ll;

int main(){
    cin.tie(0);
    ios::sync_with_stdio(0);
    
    int n; cin >> n;
    rep(i,n) {
        cout << "a";
        int x = i;
        string s = "";
        while(x > 0) {
            s += char(x % 26 + 'a');
            x /= 26;
        }
        cout << s << "an"[i == n - 1] << "\n";
    }
}