#include "bits/stdc++.h"

using namespace std;

#define pb push_back
#define mp make_pair
constexpr int INF = 1 << 29;
constexpr int MOD = 1000000007;
typedef long long ll;
typedef unsigned long long ull;

constexpr int dx[4] = {1, 0, -1, 0};
constexpr int dy[4] = {0, 1, 0, -1};

int main() {
	int N;
	cin >> N;
	for (int i = 0; i < 1 << 18; i++) {
		if (i >= N - 1) break;
		string s = "a";
		for(int j = 0; j < 18; j++) {
			if (i >> j & 1) s += "a"; else s += "b";
		}
		s += "a";
		cout << s << endl;
	}
	cout << "an" << endl;
	return 0;
}