"Drop... Drip... , Scanning, Scan Complete. ”

"Unknown alien metal alloy material, gold content 17%, copper content 32%, iron content 13%, the remaining 38% unknown substance, the object outline shape is intact, the pattern is clear, no corrosion, the detection casting age is about 700 years, the shape is a standard fan, the angle is 60 degrees, there are grooves on both sides, it is speculated to be a mosaic structure, and the complete number is six pieces. ”

It has been formed for 700 years, which means that this key is indeed left over from that era as the teacher said.

Wait a minute!

And the mosaic structure?

Nalan Xingtian looked at the two keys on both sides, he reached out to touch them, and found that the two keys were the same, one side was a very fine groove, and the other side was a subtle protrusion, very hidden, if it wasn't for the apocalypse, he thought it was just a simple pattern decoration. He tried to bring the two keys closer together, and then tapped the protrusion of one key against the groove of the other key from the front.

Click!

A crisp sound sounded, and then Nalan Xingtian slid down slightly again and pulled it down, and the two keys were completely and tightly combined together, becoming a larger fan-shaped object.

"...... this?" Timos watched Nalan Xingtian's movements on the side, and saw the two keys come together.

"The two keys actually came together. Meloti was a little surprised.

"I think I know. Nalan Xingtian looked at the two keys that were put together and said.

"What do you know?" asked Timos.

"The so-called keys are not six, but one, and each of your factions has only one part of a complete 'key'. Nalan Xingtian replied.

"A key?" Melotti wondered.

Nalan Xingtian exerted his strength slightly, and with a crisp sound of the card, the two keys were divided into two: "Yes, one key, look at this key, except for the different patterns and patterns inside the two keys, his shape and size are the same." On both sides of this fan, there is a protrusion and a groove on the other, and any combination of sides can be easily merged together in this way. ”

Nalan Xingtian experimented several times in a row in front of Timos and Meloti, and no matter how the two keys were combined, they could be combined to form a new and larger fan.

Nalan Xingtian said while fiddling with the two keys: "That is to say, according to the proportion, size and angle of this fan, each fan angle is sixty degrees, and the six keys will form a circle of three hundred and sixty degrees, and the combined circle is the real complete key." ”

Nalan Xingtian said this, and found that Timos and Meloti were looking at him blankly, and he was a little puzzled: "Is there any problem?" ”

"I mean, what are sixty degrees?" asked Timos.

"Eh, a unit of angular calculation, this fan-shaped shape, the measure of the quantity that must be rotated when you look at the two straight lines on the edge, when either of these two intersecting lines overlaps the other, is the degree, which was taught to me by a bard I met in Loulan City. Once again, Nalan Xingtian put all the problem on the bard.

He instantly realized that in this world, the so-called mathematics and geometry and other disciplines are in a state of primary enlightenment, and most people do not have the slightest cognitive concept of these.

"Well, it's a little complicated, I don't understand it too much, you move on to the point. Timos said.

Nalan Xingtian looked at Meloti, who met his gaze, and then said carefully, "I think I probably understood a little, it is this fan-shaped key, and the distance between the lower corners is as big as this key, which is the sixty degrees that Nalan Xingtian said. ”

Nalan Xingtian glanced at her appreciatively, "That's right. ”

In the end, he is a young man, and his way of thinking is not completely stereotyped, and he understands it quickly.

Then Nalan Xingtian continued: "If my speculation is correct, the six keys combined into a complete circle are the real keys, but it is unknown where this key will always open the door, and where the door is, and what is the practical method of this strange round key?"

Nalan Xingtian rubbed the precise patterns and patterns on the key, and then said: "Moreover, the six keys, the pattern of each key is completely different, if it is speculated that each key can be combined and linked at will, and the keys with different patterns are in different orders, then I think there are many ways to combine them." ”

"A lot of kinds?" Timos probably understood the meaning, and then he probably understood the combination of keys with different patterns in different orders, he thought about it slightly, but vaguely felt that there were many combinations, but he couldn't figure out how many kinds there were.

"I probably know a little bit about arithmetic, and I only know that there are many combinations, but I don't know how many there are. Meloti said.

Sure enough, the basic mathematics of the other world is incomplete, then this can only show the lack of basic education in the original world, but in such a different world, basic education is simply a fantasy.

Nalan Xingtian didn't sell Guan Zi, he continued to say his thoughts: "If you calculate according to the way of these six keys, according to the way of permutation and combination, 6*5*4*3*2*1 is equal to 720, that is to say, there are seven hundred and twenty ways to combine them. ”

"Such a powerful number of techniques, Nalan Xingtian, you are so powerful. A look of surprise flashed in Meloty's eyes.

Timos didn't understand the calculation at all, but he understood the combination of seven hundred and twenty, and he said, "Seven hundred and twenty, I don't know how much time it will take to try them one by one." ”

Nalan Xingtian rubbed the pattern on it and muttered: "This key to precision manufacturing, I think the pattern on it is related and meaningful to the text, but our current people can't understand it at all. ”

Nalan Xingtian paused and continued: "If, suppose this 'key' opens the 'door' of a treasure vault, then whether there are corresponding traps or other dangerous things set up in that treasure vault, and whether these permutations and combinations are the key to opening the 'door', if the combination is wrong, then after opening the door and getting the 'door', it is not clear whether you will be greeted by endless treasures or a catastrophe of destruction." ”

"It seems that this key in our hands is really not a simple thing, and another thing that amazes me is how knowledgeable my apprentice is. Timos exclaimed.

He knew that Nalan Xingtian was smart, and he could see it from the process of teaching Nalan Xingtian, but he didn't know the ability to use such a number of techniques.

"So, in this way, it is considered that you have found all six keys and put them together, and then found the location of the treasure, and you must find the right combination, otherwise, it will be a disaster to open the door rashly. Meloti frowned.

"I speculate that it should be like this, the treasure of the former Nine Heroes, such a cautious and precise design should also be, otherwise, what is the point of them setting such a complex key to be kept separately, and then designing such a delicate and repeated pattern on it?" Nalan Xingtian looked at the precise pattern on the key, and affirmed his thoughts even more.