#include <bits/stdc++.h>
#define rep(i, a, n) for(int i = a; i < n; i++)
#define repr(i, a, b) for(int i = a; i >= b; i--)
#define int long long
#define all(a) a.begin(), a.end()
#define chmax(x, y) x = max(x, y)
#define chmin(x, y) x = min(x, y)
using namespace std;
typedef pair<int, int> P;
const int mod = 1000000007;
const int INF = 1e12;

unsigned ww;
unsigned xor128() {
    static unsigned x = 123456789, y = 362436069, z = 521288629/*, w = 88675123*/;
    unsigned t = (x ^ (x << 11));
    x = y; y = z; z = ww;
    return (ww = (ww ^ (ww >> 19)) ^ (t ^ (t >> 8)));
}

signed main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    int n;
    cin >> n;
    vector<string> ans;
    set<string> st;
    rep(i, 0, n){
        string s = "";
        while(1){
            s = "";
            if(i != 0) s += ans[i - 1][ans[i - 1].size() - 1];
            while(s.size() < 20){
                s += 'a' + xor128() % 26;
            }
            if(i == n - 1) s[s.size() - 1] = 'n';
            if(!st.count(s)){
                st.insert(s);
                break;
            }
        }
        ans.push_back(s);
    }
    for(int ii = 0; ii < ans.size(); ii++){
        cout << ans[ii] << endl;
    }
}