gaff (npm): [![Maintainability](https://api.codeclimate.com/v1/badges/827f0c20e22646255a1f/maintainability)](https://codeclimate.com/github/rustamyusupov/project-lvl2-s487/maintainability) [![Build Status](https://travis-ci.org/rustamyusupov/project-lvl2-s487.svg?bra
Keywords: diff|calculator