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