Entering the room, there are rows of wooden barrels on one side of the wall, and the lid is very dead.

Out of curiosity, I motioned for the monkey to shine the light on. I took out a dagger and cut the seal on the barrel.

As soon as it was cut, a strong rancid smell suddenly came to my nose. I quickly waved my hand to fan the strange smell, resisted the urge to gag in my heart, pinched my nose and came up to see, the black liquid was floating something, and I couldn't see it very clearly, "Monkey, bring the flashlight closer, I can't see clearly."

By the light of the monkey, my heart immediately cooled down, and there were broken corpses fluttering in the barrel, and the filaments fluttering on the surface of the black liquid were the hair left by people. "What kind of strange custom is this" I couldn't help but exclaim, and was just about to put the lid of the wooden barrel on it, when I suddenly heard the monkey's exclamation, "Little Ke Ye, let it go."

As soon as I heard that it must not be a good thing, I reflexively glanced at it, and saw four or five fist-sized corpses drifting above the wooden cover, and the long barbs were about to stab me in the hand. I threw it to the ground in fright, shot it with my pistol, and suddenly a foul smell began to spread around. I quickly scanned my surroundings to see if there was an exit.

At this time, the wooden barrels that were still on the ground began to sound "popping", like the sound of green bamboo cracking when it meets fire. The monkey and I hurriedly turned on the flashlights, keeping an eye out for every move around us.

I could clearly see with the naked eye that the corpses had turned out of the barrels, and the smell in the cave suddenly became heavier, and the largest one was the size of a skull, and began to swarm towards me and the monkeys.

We had no way back, and we stood on the side of the wall. "Little Ke Ye, there's a hole on it" As soon as the monkey's voice fell, I raised my head and saw that it was only two or three meters away from us, and there was indeed a hole.

The monkey didn't say a word, and immediately half-squatted and asked me to go up first. Seeing that the situation was urgent, there was no time to excuse himself, but fortunately, he had practiced martial arts when he was a child, and he couldn't help himself, stepped on the monkey's shoulder, jumped to the entrance of the cave, and everything seemed to be very smooth.

The monkey below had set his coat on fire, and I handed it down, and just as the monkey's hand grabbed my hand, and when I was about to come up, there was a sudden stench from behind, and before I could think about it, my whole person was pushed down.

Rumble!

I fell the monkey, and the monkey screamed. I don't know when the zongzi that pushed me just now came over and pinched my neck. I hurriedly resisted it with both hands, and the monkey was responsible for driving away the surrounding corpses, and I couldn't hold on for long, "Zhang Yu, Zhang Yu, come and help!" I shouted.

Zhang Yu and the scarred Zagai ran in together, and as soon as the two came in, the corpses around them suddenly seemed to see ghosts, and they avoided everywhere. I saw that both of them were stained with pungent blood.

Fast! Zhang Yu shouted, took out a black handkerchief, only to see a big "Buddha" engraved on the handkerchief, which has been dyed bright red, and the blood has not dried up, Zhang Yu helped me resist the zongzi, and shouted anxiously: "Quickly wipe the blood on the body."

With a slight hesitation, I quickly complied, and the monkey was also neat. The surrounding corpses began to spread out in all directions, and the zongzi roared wildly, Zhang Yu struggled to resist it, and motioned for us to go up first.

After I, the monkey, and the three of them got to the top, Zhang Yu's big hand was loosened, and he jumped, I hurriedly handed my hand over, and the three of them worked together to pull Zhang Yu up.

Zongzi couldn't come up, screaming frantically, and didn't know how he came up just now, Zhang Yu frowned, "Let's get out of here quickly, go to the main room, the sooner we arrive, the better."

The aisle was not very long, and it didn't take long for us to reach the end, but the exit was blocked by a heavy copper door, and a key could be inserted into the keyhole to open the copper door.

On the stone wall on one side of us were embedded four wooden boxes, each with a groove in which a thing in the shape of what we see now was a Rubik's cube. It can be freely turned to form a unique shape. The grooves of the first three wooden boxes are made into tetrahedron, hexahedron, and octahedron respectively. And the groove of the last wooden box is completely neat, and it is obvious that we will make it into shape.

Look, little Ke Ye! The monkey exclaimed, pointing to the wall on the other side and shouting, and I hurriedly shone the flashlight at it. I saw that there were eight big characters left on the wall: If you need to take the key, don't take it by force. There is still a formula f+v-e=2 below.

What does that mean? Could it be that the key is in this wooden box? Thinking like this, my hand was about to grab the wooden box, but Zhang Yu immediately stopped me, "The person who wrote this is probably the person who has been following us." Presumably, the key in his mouth is in the fourth wooden box, but he doesn't know how to crack it, what is the connection between the first three regular polyhedra."

Tetrahedron, hexahedron, and octahedron are the shapes shown in the first three wooden boxes. There is also a formula left: f+v-e=2. What does this mean? I stared at it and saw that my head was too big, and I didn't have any thoughts at all. The only thing that exclamates is that it is so ingenious to make these grooves that are shaped like Rubik's cubes to turn.

Thoughts fell into a stalemate, the monkey and Zagai didn't pay much attention at all, they sat on the ground to rest, and I was also half-watching and half-looking, and Zhang Yu didn't leave his attention for a moment.

Seeing that this was not a solution, I casually said, "If you want me to say, this is very similar to the math problems we did in high school." If you think, look at the picture to find the pattern. Isn't that what math fill-in-the-blank questions look like? Give you a few pictures, and then write out the formula." I myself feel a little ridiculous to say it, but I can only explain it this way. "If you want me to say, this polyhedron is nothing more than how many faces, how many points, how many edges, and so on!". Thinking of this, my mind quickly flashed the number of points, faces, and edges of the tetrahedron to 8, 6, and 12 respectively. If f is compared to the number of points, v to the number of faces, and e to the number of edges, this formula is just satisfied.

In this way, I tried to calculate the regular pentahedron and the regular octahedron, both of which fit this formula. In this case, then the fourth wooden box should also be made into a regular polyhedron, and it should conform to f+v-e=2, but the question now is which regular polyhedron conforms to this formula.

Zhang Yu, who was standing next to him, seemed to have thought of this, his brows furrowed, and he whispered in his mouth: "If it is written according to the above formula, then there are only two regular polyhedra left that meet its conditions. One is a positive twelve, and the other is a positive twenty. Now the question is not sure which one of them is exactly? ”。 Zhang Yu said this, but his hand did not stop, but grabbed his hand towards the groove in the wooden box, and the thing shaped like a "Rubik's Cube" was taken out, and a small raised square wooden block suddenly appeared at the bottom of the groove.

I laughed at this and said, "The designer really didn't expect that as long as we had to adjust the bottom of this thing so that it was facing the little raised wooden block, it would be fine."

No way! Zhang Yu rejected me, "Even if we get it, if the result is wrong, the mechanism cannot be opened, but like the Da Vinci code, the key will be destroyed." As he spoke, Zhang Yu grabbed the thing in his hand tightly with both hands and did not move. I was very entangled in watching it, "Let me come".

After I took it, I found that this thing is much more difficult than the "Rubik's Cube", I was ready to move into a positive twenty body, but found that there was no complete figure in my mind, and when I saw the eyes of everyone, I laughed a few times, and was stunned to move into a positive twelve body.

Finally, it was done, and the thing in my hand did have a groove, right against the bulging wooden block. I exhaled and pressed it from my hand, only to hear a crunch "click", and I hurriedly released my hand and stepped back. Then it became quiet, and my heart fell to my throat, thinking that this was the end.

Syllable!

I could hear it clearly, it was the sound of iron hitting stone, and I saw a sudden opening in the bottom of the wooden box, and an iron key fell out of it. The monkey hurriedly stood up and laughed: "Little Ke Ye, I know that Chuan Ye is not wrong."

Zhang Yu picked up the key, and when he passed by me, he said in a low voice: "Why are you so sure of choosing the dodecahedron just now, it seems that I underestimated you before."

I smirked and waved my hand, my face couldn't help but feel a little hot, if I told it, I would only straighten the dodecahedron, I wonder what he would think?

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