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