cli-calculator

CLI Calculator for SonarLint technical interviews

Copyright (C) 2022 SonarSource SA

All rights reserved

Interview environment

The exercise consists in implementing an interactive text-based command line calculator.

It lasts about 3 hours with three 1-hour long "sprints". Each sprint consists of ~45-50 minutes of development and ~10-15 minutes of code reviews and feedback in-between.

Please push your full project as is at least at the end of each "sprint".

Evaluation criteria

This is your product! The intention of this exercise is to help us evaluate how you would organize yourself to deliver a clean product that addresses a common need.

We will pay special attention to these criteria, by order or priority:

• Testing
• Knowledge and pragmatic application of Clean Code principles
• Ability to take decisions and make design choices based on the desirable UX
• Ability to prioritize change requests

Tips

• Try to start simple and iterate
• Explain your work
• Relax and be yourself

Initial specification

The calculator starts with a "current" value of 0. It reads one-line-commands and executes them. Valid commands are:

• ADD <OPERAND>: add the value of operand to the current value
• SUBTRACT <OPERAND>: subtract the value of operand from the current value
• MULTIPLY BY <OPERAND>: multiply the current value by the value of operand
• DIVIDE BY <OPERAND>: divide the current value by the value of the operand
• DISPLAY: show the list of values computed since the last call to DISPLAY

Example session

In the example below, > marks user input and < marks calculator output:

> ADD 5
> MULTIPLY BY 3
> SUBTRACT 3
> DISPLAY
< 5
< 15
< 12
> DIVIDE BY 6
> DISPLAY
< 2