Код Грея

  #include <iostream>
  #include <bitset>
 
  typedef unsigned char uc;
  const int size_uc = 8*sizeof( uc );
 
  uc Gray( const uc &n )
  {
    return ( n ^ ( n >> 1 ) );
  }
 
  uc Gray_decode( uc g )
  {
    uc dg = 0;
        for (  ; g; g >>= 1 )
            dg ^= g;
   return dg;
 }
 
 int main()
 {
   uc x = 42;
   std::cout << (int)x << " = " << std::bitset<size_uc>( x );
   uc gray_x = Gray( x );
   std::cout << " --> " << std::bitset<size_uc>( gray_x )
             << " = " << (int)gray_x << "\n";
 
   std::cout << (int)gray_x << " = " << std::bitset<size_uc>( gray_x );
   uc decode_gray_x = Gray_decode( gray_x );
   std::cout << " --> " << std::bitset<size_uc>( decode_gray_x )
             << " = " << (int)decode_gray_x << "\n";
   return 0;
 }