Question

I have an character array (say char charr[5]) which contains 0/1 (char array of boolean number). Now, I want to convert the character array to 64 bit integer number (if array is {0, 0, 0, 1 , 0}, it will give 2 ). How to do that ? Is there any library functions ?

Answer 1

No, there’s no standard function for that. But it’s pretty trivial:

uint64_t pack(const uint8_t *bits, size_t n)
{
  uint64_t x = 0, value = 1 << (n - 1);

  while(n > 0)
  {
    x += value * *bits++;
    n--;
    value /= 2;
  }
  return x;
}