#include <iostream>
using namespace std;
int main()
{
 int height;
 cin>>height;
 if(height<1||height>26)
 {
  cout<<"Invalid input";
 }
 else
 {
  for(int i=1;i<=height;i++)
  {
   char letter='A'
   for(int j=0;j<i;j++)
   {
    cout<<letter<<" ";
    letter++;
   }
   cout<<endl;
  }
 }
 return 0;
}