#define _CRT_SECURE_NO_WARNINGS
#include<iostream>
#include<sstream>
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<climits>
#include<cmath>
#include<string>
#include<vector>
#include<set>
#include<map>
#include<queue>
#include<numeric>
#include<functional>
#include<algorithm>
#include<bitset>
#include<tuple>
#include<unordered_set>
#include<random>
#include<array>
#include<cassert>
using namespace std;
#define INF (1<<29)
#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define all(v) v.begin(),v.end()
#define uniq(v) v.erase(unique(all(v)),v.end())

using namespace std;




int main() {
	string ans = "NO";


	int n; cin >> n;
	rep(i,n) {
		string s;
		s += 'a';
		int x = i;
		rep(j,17) {
			s += x % 26 + 'a';
			x /= 26 ;
		}
		s += 'a';
		if (i + 1 == n)s += 'n';
		cout << s<<endl;
	}




	return 0;
}