#include<bits/stdc++.h> using namespace std; int main() { char p[26]={'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'}; int num,x=0; cin>>num; for(int i=0;i<num;i++){ for(int j=0;j<=i;j++){ cout<<p[x%26]; x++; } cout<<endl; } return 0; }