import java.util.Hashtable;

public class HashtableExample
{
    public static void main(String[] args)
    {
        //1. Create Hashtable
        Hashtable<Integer, String> hashtable = new Hashtable<>();

        //2. Add mappings to hashtable
        hashtable.put(1,  "A");
        hashtable.put(2,  "B" );
        hashtable.put(3,  "C");

        System.out.println(hashtable);

        //3. Get a mapping by key
        String value = hashtable.get(1);        //A
        System.out.println(value);

        //4. Remove a mapping
        hashtable.remove(3);            //3 is deleted

        //5. Iterate over mappings

        for (Integer key : hashtable.keySet()) {
            String mappedValue = hashtable.get(key);

            System.out.println("Key: " + key + ", Value: " + mappedValue);
        }
    }
}