Added Reverse Binary Strings (Codeforces)

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• [x] The solution I have given is my own and not plagiarized in any form.
• [x] My solution passes all the testcases within the given constraints.
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[boring-cyborg[bot]]

Hi there :wave: Congratulations on sending your first PR here :sparkles: Your PR will be reviewed soon, in the meantime it would be great if you could star :star: this repo :smiley:

[mergify[bot]]

Awesome :thumbsup:, Thanks for contributing :smiley:!