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