#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp> 
#include <ext/pb_ds/tree_policy.hpp> 
#include <ext/rope>

using namespace __gnu_pbds; 
using namespace __gnu_cxx;
using namespace std;

typedef long long ll;

#define eb emplace_back
#define pb push_back
#define mp make_pair
#define ff first
#define ss second
#define len(v) ((int)v.size())
#define all(v) v.begin(), v.end()

void io(){
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);    
    #ifdef LOCAL
        freopen("input.txt","r",stdin);
        freopen("output.txt","w",stdout);
    #endif
}
template<typename T> using oset = tree <T, null_type, less <T>, rb_tree_tag, tree_order_statistics_node_update >;
template<typename T> using MinPriorityQueue = priority_queue <T, vector <T>, greater <T> >;
template<typename T> void done(T ans) {cout << ans << "\n"; exit(0);}

auto seed = chrono::high_resolution_clock::now().time_since_epoch().count();
mt19937_64 mt(seed);

clock_t time_p=clock();
void printTime(){
    time_p=clock()-time_p;
    cerr<<"Time Taken : "<<(float)(time_p)/CLOCKS_PER_SEC<<"\n";
}


ll mod=1e9+7;
const int N = 1e5 + 5;
bool collinear(int x1, int y1, int x2, int y2, int x3, int y3) {
  return (y1 - y2) * (x1 - x3) == (y1 - y3) * (x1 - x2);
}

int32_t main(){
    io();
    int n ;
    cin >> n;
    for(int i = 0; i < (1 << n); i++) {
        int flag[20] = {0};
        for(int j = 0; j < n; j++) {
            if((1 << j) & i) {
                flag[j] = 1;
            }
        }
        if(flag[0]) continue;
        for(int j = 0; j < n; j++) {
            if(flag[j]) cout <<'b';
            else    cout << 'a';
        }
        cout << endl;
    }


}
