#include <bits/stdc++.h>
using namespace std;
string toB(int n) {
  string r;
  while (n != 0) {
    r = (n % 2 == 0 ? "0" : "1") + r;
    n /= 2;
  }
  return r;
}
void solve(int n) {
  int m = pow(2, n);
  for (int i = 0; i < m; i++) {
    string s = bitset<12>(i).to_string();
    string ans = "a";
    for (int j = 12 - n; j < s.length(); j++) {
      if (s[j] == '0')
        ans += "a";
      else
        ans += "b";
    }
    cout << ans << "\n";
  }
}
int main() {
  int a;
  cin >> a;
  if (a == 1) {
    cout << "a";
    return 0;
  }
  solve(a - 1);
  return 0;
}
