In the night, Angel continued to speak in a weak voice, getting more and more wrong.
"Next... keep walking and you will come across a tavern called 'Water and Fire'... go over and turn right, then..."
After listening to Angel's words, Richard suddenly interrupted and asked seriously: "Do you know where you are now?"
"Ah?" Angel was stunned for a moment, then looked down at the ground, "On the ground?" He looked up at the starry sky: "Under the stars?"
"..." Richard was silent for a while, exhaled helplessly, and said to Angel: "Okay."
"Ah?" Angel didn't understand.
"It's better that I take you back to White Rock Tower Academy." Richard said. From what Richard could see now, Angel's road blindness was such that even if he was given directions a hundred times, he might not be able to reach the destination smoothly. It would be better for him to send the other party back and settle the matter once and for all, so as to save the other party from having any accidents on the way back and causing unnecessary trouble.
Richard stepped forward, glanced at Angel, who was still standing there, and said, "What? You don't want to go back?"
"Uh... no... no." Angel said quickly.
"Then keep up, keep up."
"Uh, yes." Angel quickly caught up and followed step by step.
Richard and Angel, one after the other, quickly arrived at Baishi City.
Walking in Baishi City, when he reached the familiar "Salt and Fire" tavern, Richard found that the tavern was closed. However, there was still a faint sound of singing coming out of it. It was a piece he had heard before, and it was somewhat familiar. Maybe you don’t understand the meaning, but the rhythm of the song remains the same:
First it was the 2/4 beat of "strong, weak, strong, weak", then it was the 3/4 beat of "strong, weak, weak", and then it was the 6/8 beat of "strong, weak, weak, strong, weak, weak".
"Ta, tap, tap, tap..."
While listening to the music, Richard took Angel around the tavern, turned left, and continued moving forward...
Finally, the singing in the "Salt and Fire" tavern disappeared, and Richard stopped at the entrance of White Stone Tower Academy. Reaching forward and pointing his finger, Richard said to Angel behind him: "You should know how to get here now, right? You don't need me to take you back to your dormitory, right?"
"Uh, no need." Angel shook his head hurriedly.
"That's good, go in, I'm leaving."
"Uh..." Angel lowered his head and walked into the academy. He turned around and glanced at Richard secretly, and found that Richard had disappeared into the darkness. He bit his lip and walked into the depths of the college with a complicated expression.
…
Laboratory, main laboratory.
Richard returned.
Because he had solved all the trivial matters, Richard relaxed a little. He strode to the experimental table in the room, took out the five newly acquired Black Spirit Empire books from the Space Iron Ring, and began to study them.
Putting the five books on the table, Richard quickly turned to the last page and scanned the numbers on the Black Spirit Empire's logo, his eyes flashing slightly.
The five numbers are 3, 7, 24, 27, and 29. Verified according to the current world version of Licrel numbers, the palindrome numbers obtained are 33, 55, 66, 99, and 121 respectively.
The books I already owned before are:
"The Wail of the Soul", palindrome number 11;
"Blood and Fire", palindrome number 22;
"Towards Nobility", palindrome number 77;
"My Autobiography—Moratos", palindrome number 99.
In other words, among the five newly obtained books, only one is a duplicate, and four are new:
The first new book "Dark Spirit", a novel about ghosts and legends;
The second new book is "Thirty-six Days of Talk", a collection of fables;
The third new book, "Coppola's Secret", is a relatively simple wizarding book.
The fourth new book, "I was born from fire - Prometheus", is the autobiography of a wizard, similar to "My Autobiography - Moratos", but it does not contain the weird content of training male slaves.
After clearing up the books, Richard's eyes lit up. He had to say that this night was a big harvest, and what he had gained was equal to everything he had gained before.
It was previously speculated that the number behind the Black Spirit Empire book logo should be within 40. Therefore, through the Licrel number verification process, the number of palindromes obtained was only 11.
11!
Now we have obtained 8 books with palindrome numbers, and only 3 books with palindrome numbers are left.
In this way, even if the secrets hidden in the books cannot be unlocked, the general framework should still be able to be seen.
Richard's eyes were sharp.
What is the secret hidden in the book
He doesn't know the secret yet, but he has some guesses about the way to hide the mystery.
The method of hiding mysteries in books should not be a hidden text - special conditions such as being soaked in water and being burned can reveal the text. In this way, firstly, it cannot be preserved for a long time, and secondly, it has no connection with the numbers and palindromic numbers on the Black Spirit Empire logo on the last page of the book.
The numbers on the Black Spirit Empire's logo, as well as the Likriel number verification palindrome numbers, are some very special numbers. They should not be confusing information, but are related to secrets.
So…
Speaking of numbers, Richard couldn't help but think of a very common early table lookup substitution method in cryptography.
The so-called lookup table substitution method, simply put, is the codebook method: transmitting information does not use normal words, but replaces it with some seemingly meaningless numbers.
The person who receives the information must have a corresponding code book. Only by matching the numbers one-to-one according to the contents of the codebook can we get the correct information and prevent it from being intercepted and leaked midway.
This method can be considered flexible and changeable. Be careful. In order to prevent the code book from falling into the hands of the enemy and causing heavy losses, the code book can be replaced periodically. To be more careful, you can use a different book as a new code book every time you send a message.
For example, if the message sender gives the message "137, 826", it may represent the 137th and 826th words in a certain book.
The person who received the message checked the book and compared it. Different books will get different results. It may be a "success" or "failure" message, or it may be an instruction such as "attack", "retreat" or "hide". There are almost no Possibility of leaks. Of course, there are still some gaps with the encryption methods developed based on computer technology on modern earth, such as symmetric encryption of DES, 3DES, AES encryption, and asymmetric encryption of RSA, elliptical encryption, etc.
Having said that, what are the results obtained using the lookup table substitution method in the current book
Richard first picked up the book "Soul Wail" with serial number 1 and palindrome number 11. He found the 11th word in the book and found that it was the word "gram".
Then he picked up the book "Blood and Fire" with the second serial number and the palindrome number 22, and found the 22nd word in the book, which was "fruit".
The serial number is No. 3, the palindrome number is 33, "Dark Spirit", the 33rd character is "Li".
The book with the serial number 4 and the palindrome number 44 is currently unavailable and will be omitted.
The serial number is No. 5, the palindrome number is 55, "Thirty-Six Days Talk", the 55th word is "ancient".
The serial number is No. 6, "Coppola's Secret" with a palindrome number of 66, and the 66th word is the partition symbol.
The serial number is No. 7, the palindrome number is 77, "Towards Nobility", the 77th character is "Du".
The book with the serial number 8 and the palindrome number 88 is currently unavailable and will be omitted.
The serial number is 9th, and the palindrome number is 99. "My Autobiography - Moratos" has the 99th character, "er".
The serial number is 10th, the palindrome number is 121, "I was born from the fire--Prometheus", the 121st word is "Meng".
The book with the serial number 11 and the palindrome number 363 is currently missing and will be omitted.
The end result is...