There are a number of things to consider when hiring an app development company. For example, it's important to pay attention to portfolio and reputation. Also, it's better to check the experience level of engineers building your product. I work with Light IT company, I can only say that I am always happy with the result https://light-it.net/#1/

The C Programming Language By Brian W. Kernighan and Dennis M. Ritchie is imo still the best book around. It's quite old but one of its authors is the very creator of the language.and the book in general is incredibly well written and has a ton of exercises.

@shaggyx ?

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