#include <bits/stdc++.h>
using namespace std;

#include <ext/pb_ds/assoc_container.hpp> 
#include <ext/pb_ds/tree_policy.hpp> 
using namespace __gnu_pbds; 

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

int getRand(int l, int r)
{
    uniform_int_distribution<int> uid(l, r);
    return uid(rng);
}
  
#define pb push_back
#define S second
#define F first
#define f(i,n) for(int i=0;i<n;i++)
#define fast ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0)
#define vi vector<int>
#define pii pair<int,int>
#define ordered_set tree<int, null_type,less<int>, rb_tree_tag,tree_order_statistics_node_update> 
#define precise(x) fixed << setprecision(x) 

const int MOD = 1e9+7;

int mod_pow(int a,int b,int M = MOD)
{
    int res = 1;
    
    while(b)
    {
        if(b&1) res=(res*a)%M;
        a=(a*a)%M;
        b>>=1;
    }
    
    return res;
}

int n;

void go(int len,int lim,string s)
{
    if(len == n)
    {
        cout << s << '\n';
        return;
    }
    
    for(int i=0;i<=min(25,(lim+1));i++)
    {
        string t = s;
        t+=('a'+i);
        go(len+1,i,t);
    }
}

void solve()
{
   cin >> n;
   string s ="";
   go(0,-1,s); 
}

signed main()
{
    fast;
    
    int t = 1;
    
//    cin >> t;
    
    while(t--)
        
    solve();
}