#include <iostream>
using namespace std;
int main() {
	int n;
	cin >> n;
	for (int i = 0; i < n; i++) {
		for (int j = 0; j <= i; j++) {
			cout << char('A' + i);
		}
		cout << endl;
	}
}

/**************************************************************
	Problem: 1977
	User: wangyiyang
	Language: C++
	Result: Accepted
	Time:17 ms
	Memory:2072 kb
****************************************************************/