#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
// mt19937 g(chrono::high_resolution_clock::now().time_since_epoch().count());


char s[5005][5];
int hamming(int A, int B) {
    int x = 0;
    int M = 4;
    for(int i = 0; i < M; i++)
        x += (s[A][i] != s[B][i]);
    return x;
}

void solve_test() {

    int N;
    cin >> N;
    int M = 4;
    for(int i = 0; i < M; i++)  s[0][i] = 'a';
    s[0][M] = 0;

    for(int i = 1; i < N; i++) {
        for(int j = 0; j < M; j++)
            s[i][j] = s[i - 1][j];
        s[i][M] = 0;
        bool added = false;
        for(int p = 0; p < M && !added; p++) {
            for(char c = s[i - 1][p] + 1; c <= 'z' && !added; c++) {
                if(c == s[i - 1][p])   continue;
                s[i][p] = c;
                bool ok = true;
                for(int j = 0; j < i - 1 && ok; j++) {
                    if(hamming(j, i) < 2) {
                        ok = false;
                    }
                }

                if(ok) {
                    added = true;
                    continue;
                }
                s[i][p] = s[i - 1][p];
            }

            for(char c = 'a'; c < s[i - 1][p] && !added; c++) {
                if(c == s[i - 1][p])   continue;
                s[i][p] = c;
                bool ok = true;
                for(int j = 0; j < i - 1 && ok; j++) {
                    if(hamming(j, i) < 2) {
                        ok = false;
                    }
                }

                if(ok) {
                    added = true;
                    continue;
                }
                s[i][p] = s[i - 1][p];
            }
        }

        assert(added);
    }

    for(int i = 0; i < N; i++)
        printf("%s\n", s[i]);
}

int main() {
#ifdef USEFOPEN
    freopen("1.in", "r", stdin);
    freopen("1.out", "w", stdout);
#endif

    cin.sync_with_stdio(false); cin.tie(0);

    int T = 1;
//    scanf("%d", &T);
    for(int t = 1; t <= T; t++) {
        //printf("Case #%d: ", t);
        solve_test();
    }

    return 0;
}