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[Beginner, C] If we can represent true/false with 1/0, why do we need the stdbool library and boolean variables? (programming.dev)
submitted 6 months ago* (last edited 6 months ago) by to c/learn_programming@programming.dev
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I saw one example

int x = 10;
int y = 5;

bool isGreater = x > y;

printf("%d", isGreater);

But I could write this

int x = 10;
int y = 5;

printf("%d", x > y);

I am a complete beginner and I have no real reason why I would or would not want to deal with boolean variables, but I want to understand their raison d'être.

Edit: typo city

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[–] 9 points 6 months ago (2 children)

First, if you do it with an int, you’re probably using up 32bits per value.

One project I worked with stored boolean values as bits in an 8-bit int, and then used binary math to read and write individual bits from that int, with each bit representing a distinct and independent boolean variable.

Really weird, complicated, and sounds kind of dumb ... but it worked, and it was extremely memory-efficient.

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  • [–] 3 points 6 months ago*

    C++ actually does this 'optimisation' for std::vector<bool>. I say 'optimisation' because it effectively trades time for space, which is usually the opposite of what you want - space is cheap, time usually isn't. Sometimes it's a good tradeoff though - it's common in embedded development where you might only have a few kB of RAM.

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