def _count1Bits(num):
 ret = 0
 while (num > 0):
  num = (num >> 1)
  ret += 1
 return ret

def _count1Bits ( num ) : ret = 0 while ( num > 0 ) : num = ( num >> 1 ) ret += 1 return ret
find the highest bit set to 1 in an integer .