The best conversion rate | currency-conversion

A TypeScript project to catch currency conversion data and find the best possible rate for conversions.

The currency data comes from a local Mock file but can be from an API, for example.

This software does not have a user interface as the objective it's to exercise the algorithm to calculate the rates.

Execution

To execute the project, follow the steps:

Assuming you have the Node.JS instaled properly.

Dependencies

npm install

Testing

npm test

Run

npm start

Result

As a result of the execution, you should find a data.csv file in the output folder, at the root of the project, showing all shortest paths to convert each currency with their pair.

Exemple

CURRENCY_CODE	COUNTRY	AMOUNT	PATH
CAD	Canada Dollar	0.00	CAD
HKD	Hong Kong Dollar	136.00	CAD \| USD
USD	USA Dollar	79.00	CAD
CNY	China Yuan/Renminbi	725.00	CAD \| USD

Algorithm

For this project was used an implementation of Dijkstra's algorithm and the whole code can be analysed on the CurrencyGraph class.

Implementation

Taking this sample to explain my understanding of this program:

So, by this image, if I would like to convert 100 Canadian dollars to Hong Kong Dollar, I can convert by 6.16 value of rate and pay at the end 616 or could be better converting first to USD by 0.79 and 0.57 values of rate, paying 136 dollars at the end the operation, 22.08% less.

TODO

As this is an exercise program, few improovements can be made before using this in a production version:

The Dijkstra algorithm implementation can be improved using a Priority Queue and change the way that nodes are read;
It's not clear at this point the correct formula to calculate the rate above the original amount;
Some nodes doesn't have adjacents as Cayman Island Dollar for example (from the available data) so in the end of the process there will be some lines without conversion;

All these points can be discussed more to find better ways to perform the currency conversion through this approach.

arthemus/best-conversion-rate