public static String[][] getRandomDeleteANumber(String lastNumber){
		int index = (int)(Math.random() * 3);
		String[][] deleteNumbers = { {""},
			 {""},
			 {""},
			 {""},
			 {""}
			 };
		String s = lastNumber.substring(lastNumber.length() - 1 - index, lastNumber.length() - index);
		String[] a = { s };
		deleteNumbers[deleteNumbers.length - 1 - index] = a;
		return deleteNumbers;
	}