Billion Dollar Question

Instructions

Problem Statement

You have been asked to find the top x billionaires by net worth in a given set of countries (number of countries = N). To implement that, you have been given access to an API that returns the details of the billionaires by country.

To simplify accessing the API, you can use the ims/billionairehub client connector to connect to the API which returns details of the billionaires by country.

import ims/billionairehub;

# Client ID and Client Secret to connect to the billionaire API
configurable string clientId = ?;
configurable string clientSecret = ?;

public function getTopXBillionaires(string[] countries, int x) returns string[]|error {
    // Create the client connector
    billionairehub:Client cl = check new ({auth: {clientId, clientSecret}});

    // TODO Write your logic here
    return [];
}

Constraints

• 1 <= N <= 5
• 1 <= x <= 10

Example 1

Input

Countries: ["United States"]
Limit: 3

Output

["Elon Musk", "Jeff Bezos", "Bill Gates"]

Example 2

Input

Countries: ["China", "India"]
Limit: 5

Output

["Mukesh Ambani", "Gautam Adani & family", "Zhong Shanshan", "Zhang Yiming", "Ma Huateng"]

Test Environment

• Client ID and Client Secret to connect to the billionaire API have been provided to you in the tests/Config.toml. You can use them to initialize the client.
• Use bal test to run and test your implementation.

Hints

• ims/billionairehub package's client can be used to invoke the get billionaires by country API. You can use the getBillionaires("<country>") remote method specifically.
• You can find the richest people per country first and then combine them to find the top x
• Query expressions will be convenient for filtering and sorting

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Source

This is an exercise to introduce users to using Ballerina HTTP service data binding