AtCoder vs. Codeforces vs. DojoCode vs. jQuery Comparison Chart

Codeforces is a project joining people interested in and taking part in programming contests. On one hand, Codeforces is a social network dedicated to programming and programming contests. On the other hand, it is a platform where contests are held regularly, the participant's skills are reflected by their rating and the former contests can be used to prepare. Codeforces constantly develops and we plan to improve the platform to give the participants the opportunity to organize their own contests, filling the project with learning content, developing Codeforces as a training and learning platform. Contests are regularly held on Codeforces. Participating in them is free and open to everybody. Every month we organize approximately six contests. To participate, you have to be registered on the site (if you have an OpenID or a Gmail account, then you won't even have to memorize the password) and register for the oncoming contest. Make sure that you are present in the list of the users.

jQuery is a fast, small, and feature-rich JavaScript library. It makes things like HTML document traversal and manipulation, event handling, animation, and Ajax much simpler with an easy-to-use API that works across a multitude of browsers. If you're new to jQuery. Return a collection of matched elements either found in the DOM based on passed argument(s) or created by passing an HTML string. All the aspects of the API that were deprecated in the corresponding version of jQuery. These methods get and set DOM attributes of elements.