Create size_of_file.cpp

[Ayishabanu]

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🚨Please review the guidelines for contributing to this repository.

• Make sure your files are in the right folder!
• Make sure you add the extension of the file (.cpp, .python, .java, etc).
• If your code is a solution for a code problem, please tell which one.
• Make sure your code is working, test for a lot of cases.

Description

❤️ Thank you!

[larissalages]

Can you put the file inside the specific folder and add the .cpp extension on the name? thanks!