public static void main(String[] args)
	{
		SequentialSearchST<String, Integer> st = new SequentialSearchST<String, Integer>();
		for (int i = 0; !StdIn.isEmpty(); i++)
		{
			String key = StdIn.readString();
			st.put(key, i);
		}

		// print keys

		for (String s : st.keys())
			StdOut.println(s + " " + st.get(s));

		for (String s : st.keys())
			st.delete(s);

		if (st.isEmpty())
			System.out.println("Successfully deleted all items");
		else
			System.out.println("Unsuccessful in deleting all items");
	}