#include <bits/stdc++.h>
int main() {
  int a;
  std::cin >> a;
  char b[a];
  for (int i = 0; i < a; i++) {
    b[i] = 'a';
  }
  b[a] = '\0';
  std::cout << std::string(b);
  for (int i = 1; i < a; i++) {
    std::cout << "\n";
    b[a - i] = 'b';
    std::cout << std::string(b);
    b[a - i] = 'a';
  }
}
