calculate number of bits set in byte

Question

I am interested, which is the optimal way of calculating the number of bits set in byte by this way

template< unsigned char byte > class BITS_SET
{
pub         


        

Answer 1

For just a single byte value, the fastest way is to store the answer in an 256 byte array that you index with the value. For example, bits_set[] = {0, 1, 1, 2, ...