I Have a Big Problem with My Hogwarts

"Attention, you'd better not take advantage of a question that has no answer or you don't know the answer, if you ask a question that you can't answer yourself, it means you lose, which means you are not eligible for Ravenk Law's admission. If you ask a question and I don't answer it within five minutes, that means I'm losing, and then I'm acknowledging your wisdom on behalf of Ravenclaw."

The Eagle Knocker finished its rules, then announced, "You can ask questions now."

Lynn didn't immediately try to ask questions, but stood there and thought calmly.

The Eagle Knocker was created by Ravenclaw, and its intelligence in riddles is equal to the extreme, and the ability to solve puzzles is the same as the ability to solve riddles.

But this so-called extreme can only represent the extreme of Ravenclaw's single person, which means that the level of puzzle-solving of Eagle Door Knocker is similar to that of Ravenclaw himself.

Moreover, this knocker has not been resting on its laurels. The things and theories it understood only lasted a thousand years ago. Obviously, it has some channel to understand the changes in the outside world. Otherwise, it is impossible that the same question has not been asked for nearly a thousand years. .

Although Lin En was a teacher in his previous life, he was just a new language teacher. He had no interest in riddles or anything, and he didn’t know much about some problems on the Internet. It's not a simple matter.

The rules of the door knocker blocked his chance to ask some unsolved mysteries of the world (in fact, even if he could ask him, he wouldn't remember what the various unsolvable questions were, unless it was a professional, who would be fine if he was idle? remember this?).

He thought about it for a long time, and the eagle door knocker didn't urge him. Finally, Lynn decided to ask a question he had seen on the Internet to test the water.

"If 1=5, 2=15, 3=215, 4=2145, then 5=how much?"

The knocker eagle didn't hesitate to hear Lynn's question, it said without hesitation.

"5=1."

The first question is over. The door knocker eagle did not enter Lynn's trap, but he was not frustrated. After all, it was just a matter of opportunistic use to test the water, and Lynn did not have much hope.

"You still have two chances." Knocker eagle said coolly, it is not a ruthless riddle machine, it is obvious that Ravenclaw also gave it emotion when creating it, so that it can also experience pride and satisfy such emotions.

Lynn frowned and thought carefully.

This knocker also thinks like a human, but it is sensible enough to avoid most of the fog attached to the surface in the riddles, that is to say, those riddles that are similar to brain teasers are not difficult for it at all .

The pleasant way of thinking has its advantages, but it also has its great flaws.

Lynn pondered for a long time, and suddenly he came up with a question, but before asking this question, he still needed to confirm one thing with the knocker.

"Is your brain given to you by Ravenclaw, exactly like a human brain rather than a machine?"

"If you want me to answer, this also uses up an opportunity for a question."

Lynn didn't care about it. If he was sure about this, and if the problem couldn't stun the eagle knocker, then he would be completely lost, and it would be the same for him whether there was a chance or not.

"Can."

"Of course my mind is exactly the same as that of a human being, only the same as my master Rowena Ravenclaw, the wise man among the human beings, that is to say, smarter than a normal person, as for a machine? How can a machine have a brain, It's dead."

The door knocker eagle said proudly, as if he was proud of being able to have the same wisdom as his master.

Immediately, Lynn had a certainty in his heart. Since the door knocker eagle's calculation method is still the human brain, he will win this time.

With a smile on his face, he gave the knocker a math problem

"Use the ten numbers 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9 to form a five-digit number. How many five-digit numbers are there with three odd numbers and two even numbers? indivual?"

This is the only high school math problem that Lynn remembers. Because he was sick and absent from school for a period of time, he missed a few lessons about the solutions and formulas of permutations and combinations taught by the math teacher. The first position fell, so he made up for the knowledge points and wrote this typical example on the first page of the wrong book, so that he could see it at first glance every time he opened it. , so it will not be forgotten until now.

The Eagle Knocker was silent.

The first time he heard this question, he thought about trying them one by one, and how many numbers he would try. However, before it arrived, he desperately discovered that there were so many possibilities, and he absolutely couldn't within five minutes. Solve the problem!

Even if the door knocker eagle can keep up with the times, it is limited to the magic world, and no one in the magic world has ever learned the mathematical problem of permutation and combination.

Even Muggle-born wizards say that they will say goodbye to ordinary society after the age of 11, and they have no chance to touch this part of mathematics.

It thought silently for another three minutes, but still didn't find any confusing information in the question, as if this thing could not get the answer at all except by listing the possibilities one by one.

"You fouled!"

Knocker said with certainty, "There is an answer to this question, but no one can tell the answer within five minutes, not even five hours!"

Lynn looked at the knocker eagle with a smile, he knew he had won.

"I can give you the answer now. There are a total of 11,040 numbers that meet the conditions."

Knocker Eagle fell silent again, for a while it couldn't judge whether the answer given by Lynn was right or wrong.

"How did you get the result? Counted in advance?"

"Who would be idle to count this? This is a mathematical problem. As long as you learn the formula and method, you can easily get the result by putting the numbers in."

Lynn looked at the knocker eagle, who was very confused by his statement, and knew that it had no modern education and could not understand what he said.

"Then what if you can't be sure if the answer I said is correct? Who wins?"

The knocker eagle struggled for a long time, and finally it said: "I have a way to judge whether you are right or wrong, but it takes time."

Lynn was shocked when he heard it: "Don't you plan to count all the numbers out one by one?"

"To verify that your answer is correct, of course."

"But how long will it take you?"

The door knocker made an estimate and said hesitantly, "It should take about five days."

"How can you just use your brain to make sure that the numbers in the column will not repeat?"

"I have my own way."

Seeing that this is the eagle's brain, he just wants to personally verify whether the numbers that Lynn said are correct, which makes him feel like shooting himself in the foot.

"Is there no other way?" he asked reluctantly.

But this stupid eagle just admits the truth: "I have to verify your answer myself, otherwise I will not recognize you."

"As you like."

Lynn has nothing to do, but it's only five days. Now it's the fourteenth of September, and five days later, it's the nineteenth.

That day was when he went to Dumbledore for the first time. There were still three days before the time node returned to normal, and he could wait for these five days.