#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  cin >> n;
  if (n == 1) cout << "a" << endl;
  if (n == 2) {
    cout << "aa" << endl;
    cout << "ab" << endl;
  }
  if (n == 3) {
    cout << "aaa" << endl;
    cout << "aab" << endl;
    cout << "aba" << endl;
    cout << "abb" << endl;
  }
}
