#include <bits/stdc++.h>
using namespace std;
void solve() {
  int n;
  cin >> n;
  vector<string> vs;
  for (int i = 0; i < n; i++) {
    string str = "";
    for (int j = 0; j < n - 1; j++) {
      str += 'a';
    }
    char ch = 'a';
    str += (ch + vs.size());
    vs.push_back(str);
  }
  for (int i = 0; i < n; i++) cout << vs[i] << endl;
}
int main() {
  solve();
  return 0;
}
