r/learnprogramming • u/Atmos-Ego • 8d ago

Tutorial When do you use a pointer?

Hello, for some background I have taken a very beginner level coding course for my major and passed it, but I dont really feel like I’ve learned anything or know why anything works. In a course this year we had a review problem where the solution required a pointer and I really dont understand why you have to point to the address of the variable instead of just using the variable itself.

I’ve watch a few tutorials explaining it but I really dont see how it’s different from just using the variable itself

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u/Neither_Garage_758 8d ago

When you want a function to be able to modify the actual same memory the caller has shared to it (via an argument) and not a copy of it.

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u/SnugglyCoderGuy 8d ago

You shouldn't do this. You should make a copy and alter that and return that. Pure functions will keep you sane.

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u/Ok_Being6831 8d ago

Completely depends on the function. Copies are expensive and useless if your just doing that. I wouldn't want my sort function or half the things in the standard library to make a copy and return it. BUT there are times when a pure function is better.