#include <bits/stdc++.h>
using namespace std;
int main() {
  int N;
  cin >> N;
  for (int bit = 0; bit < (1 << N - 1); ++bit) {
    for (int i = N - 1; i >= 0; --i) {
      if (bit & (1 << i)) {
        cout << 'b';
      } else {
        cout << 'a';
      }
    }
    cout << endl;
  }
}
