#!/usr/bin/env cscript
#include <stdio.h>
#include <string.h>

int
main(int argc, char *argv[]) {
	char column_index[3 + 1];

	strcpy(column_index, "A");


	for (int i = 0; i <= 52; i++) {
		column_index[strlen(column_index) - 1] += 1;
		puts(column_index);
	}
}