code: public static int hamming(TupleDesc_B a, TupleDesc_B b ) {
  		int score = 0;
  		final int N = a.data.length;
  		for( int i = 0; i < N; i++ ) {
  			score += hamming(a.data[i] ^ b.data[i]);
  		}
  		return score;
  	}
docs: Computes the hamming distance between two binary feature descriptors
  
  @param a First variable
  @param b Second variable
  @return The hamming distance