#include <bits/stdc++.h>
using namespace std;
using ll = long long int;
int main(int argc, char *argv[]) {
  int n;
  cin >> n;
  string ans;
  if (n == 1) {
    cout << "a" << endl;
  } else if (n == 2) {
    cout << "aa" << endl;
  } else if (n == 3) {
    cout << "aaa" << endl;
    cout << "aab" << endl;
    cout << "aba" << endl;
    cout << "abb" << endl;
    cout << "abc" << endl;
  } else {
    cout << "test" << endl;
  }
  return 0;
}
