WEEK-2-TASK-NODE

Engineering Problems

This repo contains the duplicate transactions problem you should be able to solve in a reasonable amount of time. It tests your understanding of JavaScript fundamentals.

Running tests

First, you need to install the dependencies for the project by running

yarn

Then, you can run the tests by running

yarn test

While in active development, you can run the tests by running

yarn test --watch

Stretch Goals

You can also choose to solve this challenge in typescript by changing the file extension of the .js file in the src folder to .ts. i.e rename src/duplicate-transactions.js to src/duplicate-transactions.ts

Your file would be typechecked when you run the test. This project is already configured to run the tests either in js or ts.

Duplicate Transactions

In this exercise, we will be looking for duplicate transactions. This is a common problem in financial systems.

Sometimes when a customer is charged, there is a duplicate transaction created. We need to find those transactions so that they can be dealt with. Everything about the transaction should be identical, except the transaction id and the time at which it occurred, as there can be up to a minute delay.

Find all transactions that have the same sourceAccount, targetAccount, category, amount, and the time difference between each consecutive transaction is less than 1 minute and put them in groups.

Input

An array of transaction objects, with an id, sourceAccount, targetAccount, amount, category, and time. You can assume that all parameters will always be present and valid. However, the incoming transactions are not guaranteed to be in any particular order.

Output

A list of all the duplicate transaction groups, ordered by time ascending. The groups should be sorted in ascending order of the first transaction in the group.

Constraints

You cannot use any third party modules. i.e You should not modify the package.json file.