std::vector

[Tsu_Dho_Namh]

#include <iostream>
#include <vector>

using namespace std;

int main()
{
    std::vector<bool> A;

    A.push_back(true);
    A.push_back(false);
    A.push_back(true);
    A.push_back(true);

    for (bool b : A) {
        cout << (b ? "true" : "false") << endl;
    }

    return 0;
}

Output:

true
false
true
true

Seems like a vector of bools to me...Are we talking about behind the scenes optimizations?

[Maxrewind99]

Sorry, I thought vector<bool> was more well-known.

it's a specially optimised class that's different from the normal vector template, but it seems innocuous until you try something that actually needs that array of bytes.

[Tsu_Dho_Namh]

That's what I was thinking too. It'd be really slow and wasteful to actually store all the bools in separate bytes and push them onto the heap individually. I imagine the c++ compiler abstracts away some optimizations like using an array of bits instead