example for https://notion.so/be1b2932260e4e06b5777d4f74c56461 (made with https://codeeval.dev)

main.cpp

#include <iostream>
#include <string>
#include <bitset>

int main(int argc, char **argv) {
    int a = 0b0101;
    a    |= 0b1101;

    std::cout << "a = " << std::bitset<8>(a) << std::endl;
}