#include <bits/stdc++.h>
using namespace std;
void file() {}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  file();
  int n;
  cin >> n;
  string s = string(n, 'a');
  cout << s << "\n";
  for (int i = 1; i < n; ++i) {
    string t = string(n, 'a');
    t[n - 1] = 'a' + i;
    cout << t << "\n";
  }
}
