code: boolean checkPaddingBytes(QrCode qr, int lengthBytes) {
  		boolean a = true;
  
  		for (int i = lengthBytes; i < qr.corrected.length; i++) {
  			if (a) {
  				if (0b00110111 != (qr.corrected[i] & 0xFF))
  					return false;
  			} else {
  				if (0b10001000 != (qr.corrected[i] & 0xFF)) {
  					// the pattern starts over at the beginning of a block. Strictly enforcing the standard
  					// requires knowing size of a data chunk and where it starts. Possible but
  					// probably not worth the effort the implement as a strict requirement.
  					if (0b00110111 == (qr.corrected[i] & 0xFF)) {
  						a = true;
  					} else {
  						return false;
  					}
  				}
  			}
  			a = !a;
  		}
  
  		return true;
  	}
docs: Makes sure the used bytes have the expected values
  
  @param lengthBytes Number of bytes that data should be been written to and not filled with padding.