#include <bits/stdc++.h>
using namespace std;
int n;
int main() {
  cin >> n;
  for (int i = 0; i < n; i++) {
    char a[12] = {0};
    int tmp = i;
    for (int j = n - 1; j >= 0; j--) {
      if (tmp % 2)
        a[j] = 'b';
      else
        a[j] = 'a';
      tmp /= 2;
    }
    cout << a << endl;
  }
}
