#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
#define F first
#define S second
#define pii pair<int, int>
#define eb emplace_back
#define all(v) v.begin(), v.end()
#define rep(i, n) for (int i = 0; i < n; ++i)
#define rep3(i, l, n) for (int i = l; i < n; ++i)
#define chmax(a, b) a = max(a, b)
#define chmin(a, b) a = min(a, b)
#define out(a) cout << a << endl
#define outa(a, n) rep(_, n) cout << a[_] << " "; cout << endl
#define SZ(v) (int)v.size()
#define inf (int)(1e9+7)

int main() {
    vector<string> v;
    v.eb("a");
    v.eb("aa");
    rep(i, 26) { string tmp = "a"; tmp += (char)('a' + i); tmp += 'a'; v.eb(tmp); }
    rep(i, 26) rep(j, 26) {
        string tmp = "a";
        tmp += (char)('a' + i);
        tmp += (char)('a' + j);
        tmp += 'a';
        v.eb(tmp);
    }
    rep(i, 26) rep(j, 26) rep(k, 26) {
        string tmp = "a";
        tmp += (char)('a' + i);
        tmp += (char)('a' + j);
        tmp += (char)('a' + k);
        tmp += 'a';
        v.eb(tmp);
    }
    rep(i, 26) rep(j, 26) rep(k, 26) rep(l, 26) {
        string tmp = "a";
        tmp += (char)('a' + i);
        tmp += (char)('a' + j);
        tmp += (char)('a' + k);
        tmp += (char)('a' + l);
        tmp += 'a';
        v.eb(tmp);
    }
    //outa(v, SZ(v));
    //out(SZ(v));
    int n;
    cin >> n;
    rep(i, n - 1) {
        out(v[i]);
    }
    out("an");
}