Convert bitset<64> to quint8

Question

I have a bitset<64> (16bit serial and 48bit timestamp), which I want to write to quint8 *data .

When the bitset<64>looks like:

1111001010100101...

I want data to look like:

data[0] = 11110010
data[1] = 10100101
...

Would be thankful if somebody could help me to implement that.

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Geezer Geezer · Accepted Answer · 2018-08-29T12:53:16

If I understood you correctly then this accomplishes what you ask:

#include <iostream>
#include <bitset>

int main()
{
    std::bitset<64> bits64{0b0111101111011001110011010101110001111011110110011100110101011100};

    /*
    01111011
    11011001
    11001101
    01011100
    01111011
    11011001
    11001101
    01011100
    */

    for (auto i = 7; i >= 0 ; i--)
        std::cout << std::bitset<8>{bits64.to_ullong() >> (i * 8)} << std::endl;

    return 0;
}

Output:

You can change the for loop statement to make it emit in whatever ordering of bytes you choose.

The key thing is employing the shift operator (<< or >>) on the integral value.

Convert bitset<64> to quint8

1 Answers