Extracting bits using bit manipulation

Question

I have a 32-bit unsigned int and I need to extract bits at given positions and make a new number out of those bits. For example, if I have a 0xFFFFFFFF and want bits 0,10,11 my

Answer 1

Beware, untested code:

for(i = 0; i < count; i++) 
{
    bitmask = 1 << positions[i];
    bit = (bytes & bitmask)!=0;
    result = (result << 1)|bit;
}