#include <iostream>
#include <iomanip>

unsigned grayToBinary(unsigned g) {
  g^=(g>>16);
  g^=(g>> 8);
  g^=(g>> 4);
  g^=(g>> 2);
  g^=(g>> 1);
  return g;
}

unsigned binaryToGray(unsigned b) {
  unsigned g((b>>1)^b);
  return g;
}

int main() {
  unsigned n(0);

  for(unsigned i(0);i<84;i++) {
    unsigned j=i+84;

    unsigned ig(binaryToGray(i));
    unsigned jg(binaryToGray(j));

    std::cout << "i,j = " << i << ", " << j << ", ig,jg = " 
	      << std::hex << ig << ", " << jg << std::dec << std::endl;

    for(unsigned k(0);k<32;k++) {
      if((ig&(1<<k))!=(jg&(1<<k))) {
	std::cout << "Bit " << k << " not indentical" << std::endl;
	n++;
      }
    }
  }

  std::cout << "n = " << n << std::endl;
  return 0;
}