#include <iostream>     // Input/output stream objects
#include <fstream>      // File stream objects
#include <sstream>      // String stream objects
#include <iomanip>      // Input/output manipulators
#include <string>       // String class and functions
#include <vector>       // Dynamic array
#include <list>         // Doubly linked list
#include <set>          // Set container
#include <map>          // Map container
#include <queue>        // Queue container
#include <stack>        // Stack container
#include <algorithm>    // Algorithms on sequences (e.g., sort, find)
#include <cmath>        // Mathematical functions
#include <climits>      // LLONG_MAX, LLONG_MIN
#include <ctime>        // Date and time functions
#include <cstdlib>      // General purpose functions (e.g., memory management)
#include <cstring>      // C-style string functions
#include <cctype>       // Character classification functions
#include <cassert>      // Assert function for debugging
#include <exception>    // Standard exceptions
#include <functional>   // Function objects
#include <iterator>     // Iterator classes
#include <limits>       // Numeric limits
#include <locale>       // Localization and internationalization
#include <numeric>      // Numeric operations (e.g., accumulate)
#include <random>       // Random number generators
#include <stdexcept>    // Standard exception classes
#include <typeinfo>     // Runtime type information
#include <utility>      // Utility components (e.g., std::pair)
#include <bitset>

using namespace std;

#define FOR(i, a, b) for(int i = a; i < (b); i++)
#define FORE(i, a, b) for(int i = a; i <= (b); i++)
#define all(x) begin(x), end(x)
#define sz(x) (int)(x).size()
typedef long long ll;
typedef pair<int, int> pii;
typedef vector<int> vi;
#define x first 
#define y second
#define mp make_pair
#define PI 3.141592653
#define compress(coord) sort(all(coord)), coord.resize(unique(all(coord)) - coord.begin())
const double eps = 1e-9; // x < eps (x <= 0) x < -eps (x < 0)
const ll inf = LLONG_MAX;

int n, curcol = 1, add = 1;
vector<string> block;
vi idx(5);
int main() {
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
    cin >> n;
    FOR (i, 0, 26) {
        string temp = "";
        temp.push_back('a'+i);
        temp.push_back('a'+i);
        block.push_back(temp);

        temp.pop_back();
        temp.push_back('a'+i+1);
        block.push_back(temp);
    }
    block.pop_back(); // take z{ out

    int cnt = 0;
    while (true) {
        for (int id: idx) cout << block[id];
        cout << endl;
        cnt++;
        if (cnt == n) break;

        idx[0] += add;
        if (idx[0] == sz(block) || idx[0] == -1) {
            if (idx[0] == sz(block)) idx[0] = sz(block) - 1, add = -1;
            else idx[0] = 0, add = 1;

            if (idx[curcol] == sz(block) - 1) curcol++;
            idx[curcol]++;

            for (int id: idx) cout << block[id];
            cout << endl;
            cnt++;
            if (cnt == n) break;

            idx[curcol]++;
        }
    }
    return 0;
}