Instructions

In this exercise you'll be writing code to keep track of international dialing codes via an international dialing code hashmap.

The map uses an integer for its keys (the dialing code) and a string (country name) for its values.

You have 11 tasks which involve dialing-codes.

1. Create a pre-populated hashmap

There exists a pre-populated hashmap which contains the following 3 dialing codes: "United States of America" which has a code of 1, "Brazil" which has a code of 55 and "India" which has a code of 91. Define the countries var to store the pre-populated hashmap:

2. Add a country to a map

Add "United Kingdom" with a dialing code of 44 to the map created in task 1:

3. Get the country name matching a country code

Retrieve the name of the country with dialing code 55

4. Update a country name

Change the name of "United States of America" to "Les États-Unis":

5. Check that a country exists in the map

Check that a record for Brazil exists in the map created in task 1

6. Attempt to update name of country that is not in the map

Try to change the name of a country with a code that is not in the map e.g. 999. This should result in no change to the map:

7. Remove a country from the map

Remove India from the map:

8. Find the country with the longest name

Process the values in the map to find the one with the longest name: