stack overflow is the largest, most trusted online community for developers to learn, share​ ​their programming ​knowledge, and build their careers.

a computer science portal for geeks. it contains well written, well thought and well explained computer science and programming articles, quizzes and practice/competitive programming/company interview questions.

github is where over 100 million developers shape the future of software, together. contribute to the open source community, manage your git repositories, review code like a pro, track bugs and features, power your ci/cd and devops workflows, and secure code before you commit it.

well organized and easy to understand web building tutorials with lots of examples of how to use html, css, javascript, sql, python, php, bootstrap, java, xml and more.

codingame is a challenge-based training platform for programmers where you can play with the hottest programming topics. solve games, code ai bots, learn from your peers, have fun.

learn to code in python, c/c++, java, and other popular programming languages with our easy to follow tutorials, examples, online compiler and references.

the ioi is the most prestigious computer science competition in the world for secondary school students. unesco and ifip are patrons. the contest consists of two days of computer programming and solving various tasks of algorithmic nature. students at the ioi compete on an individual basis, with up to four students competing from each participating country.

a complete list of all ascii codes, characters, symbols and signs included in the 7-bit ascii table and the extended ascii table according to the windows-1252 character set, which is a superset of iso 8859-1 in terms of printable characters.

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