/* 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
	{
		HashMap<String,ArrayList<String>> map = new HashMap<>();

        map.put("a", new ArrayList<String>(Arrays.asList("one")));
        map.get("a").add("two");

        System.out.println(map);
	}
}