Question

I need to shift an unsigned int to the right more than 32 times and still get a proper answer of zero instead of the random or original number. E.g 8 >> 40 should = 0 but it returns a random number.

I understand a loop that shifts one place right at a time would solve this problem as it would fill in zeros as it went. However my current code for this doesn’t work for some reason. What am I doing wrong?

unsigned int shiftR(unsigned int a, unsigned int b) {
  unsigned int i=0;
  while (i < b) {
      a >> 1;
      i++;
  }
  return a;
} 

This gives me a compile warning that it has no effect ( a >> 1;). How come?

Thanks!

Answer 1

You want to use a >>= 1; or a = a >> 1; this is because a >> 1 shifts a to the right once and returns the result. It doesn’t assign the result to a