#include<iostream>
using ll = long long;
using namespace std;
int main(){
    char table[]={'a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z'};
    ll n;
    cin >> n;
    for(ll i=2;;i++){
        ll top=0;
        do{
            for(ll j=0;j<i;j++)    cout << table[(j+top)%26];
            cout << endl;
            if(!n--) return 0;;
            top+=(i-1);
        }while(top%26!=0);
    }
    return 0;
}