Explain the following C++ method

Question

#define XL     33           
#define OR      113          
#define NOR     313     
#define TN     344  

int to_bits(int critn,char *mask)
{
       unsigned int x;
             


        

Answer 1

  *mask = (char)(0x80 >> (x % 8));  

The value x is masked so that only the lower three bits remain. The value 0x80 is shifted to right by the remaining number. The result is assigned to the value where mask points to.

   return (int)(x >> 3);    // fast divide by 8     

x is divided by eight. The result is the reutrn value of the method.