/* package whatever; // don't place package name! */

import java.util.*;
import java.lang.*;
import java.io.*;

/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		String a="B";
		int b = 1;
		int index = 0;
	    String str = "";
	    final int cst = 2*(b-1);
	    for(int i=0;i<b;i++){
	        index = i;
	        int add = 2*(b-1-i);
	        int c=0;
	        while(index<a.length()){
	        	System.out.println(str+" "+index+" "+i);
	            str += Character.toString(a.charAt(index));
	            if(i==0 || i==b-1)
	                index += cst;
	            else if(c%2==0)
	                index += add;
	            else
	                index += cst - add;
	            c++;
	        }
	    }
	    System.out.println(str);
	}
}