static Scanner in = new Scanner(System.in);
static String pattern = "ZYXWVUTSRQPONMLKJIHGFEDCBABCDEFGHIJKLMNOPQRSTUVWXYZ";
public static void main(String[] args) {
int line = in.nextInt(), col = in.nextInt();
for(int i=0;i<line;i++) {
System.out.println(pattern.substring(25 - i, 25 - i + col));
}
}