#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  cin >> n;
  for (int(i) = 0; (i) < (pow(2, n)); ++(i)) {
    if (i & 1) continue;
    for (int(j) = 0; (j) < (n); ++(j)) {
      if (i & (1 << j))
        cout << 'b';
      else
        cout << 'a';
    }
    cout << endl;
  }
}
