#include <bits/stdc++.h>
using namespace std;
void solve() {
  string s = "aaaaaaaaaa";
  int n;
  cin >> n;
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < n; j++) {
      cout << s[j];
    }
    cout << "\n";
    for (int j = i + 1; j < s.size(); j++) s[j] += i + 1;
  }
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  solve();
  return 0;
}
