#!/usr/bin/env cscript
#include <stdio.h>
#include <string.h>
#define ALPHABET "ABCDEFGHIJKLMNOPQRSTUVWXYZ"

int
main(int argc, const char *argv[]) {
	char column_string[3 + 1], next_column_string[3 + 1], *needle_column_string;

	strcpy(column_string, "A");

	for (int i = 0; i < 78; i++) {
		puts(column_string);
		
		for (needle_column_string = &column_string[strlen(column_string) - 1];
		     column_string <= needle_column_string; needle_column_string--) {
			if (*needle_column_string == 'Z' + 1) {

			} else {
				*needle_column_string += 1;
			}
		}
	}

	return 0;
}