The four of them ate beef noodles together, and after eating them, they began to share their information, and now they have each group been given an egg.

Zeng Qin: "Sister Qian, neither of us has pockets on us, and it is very inconvenient to hold eggs, so let you keep them." ”

Qi Qian agreed, and then let Yu Luo, the only one with a pocket here, hold it.

Zeng Qin said that they kept going around the playground and turned to the back mountain, but the back mountain was stopped by an iron gate.

Yu Luo said: "You go to the iron gate later, if it is really forbidden and you can't go, the staff should stop you, if the staff doesn't stop the inside, it means that you can go in." ”

Cai Yi: "Yes, depending on the attitude of the staff, I said that there is something wrong, the iron door is very dilapidated, and it is full of rust, but the door lock is new, and we should need to find the lock next." ”

Qi Qian: "Houshan is indeed a good place to hide treasures and people, you go to Houshan to have a look first, and we will continue to look for things in the playground." ”

The four of them discussed and set off separately again.

Qi Qian and Yu Luo wandered to the roller coaster, and Qi Qian proposed to wander around here a few times.

Then they groped around, but unexpectedly, the dilapidated roller coaster began to kick in.

They just stood down and watched the roller coaster spin around slowly, spinning and flying around.

Qi Qian patted his chest: "It's so dangerous, we didn't sit stupidly just now." ”

Yu Luo: "Well, this roller coaster turned out to be good. ”

Then the roller coaster came back after a lap and nothing happened, they maneuvered the roller coaster for another lap and still didn't see anything.

Qi Qian: "Shouldn't this let us sit again, there are no staff around, and I don't know whether this roller coaster is good or bad." ”

Yu Luo shook his head: "It shouldn't be a roller coaster, it's too risky, Sister Qian, you wait to control the roller coaster, I'll go over there and have a look." ”

The two did the division of labor, Qi Qian manipulated the roller coaster again, Yu Luo stood under the roller coaster and watched, after turning many times, his eyes lit up, and he said to Qi Qian: "Sister Qian, Sister Qian, come and see." ”

Qi Qian ran over: "What's wrong?" ”

"The roller coaster stops and turns regularly every time, so let's build a coordinate axis."

Yu Luo took out the previous limestone from his pocket and drew it on the ground, I just used my mobile phone to time, the time of each form and the stay time of the roller coaster, and I came up with several sets of numbers.

"And if these groups of numbers have a decimal system, they correspond to these points on the coordinate axis, and then we connect these points, which is an arc, an arc that laughs."

Qi Qian: "The arc of laughter, you take out two eggs." ”

Placing the two eggs in place, Qi Qian drew an arc under the eggs with limestone.

Qi Qian: "What is this like?" ”

Yu Luo: "A smiling face." ”

"That's right, a smiling face, then I know, there's a place, come with me."

As they wandered around in the morning, they saw a sign with a smiling face in one place, and it was next to the clown pattern.

The clown pattern is on the wall, next to which is a whackle-smashing machine.

Yu Luo saw that there were two holes in the machine, and tentatively put two eggs in the holes.

The next scene surprised them.

They heard the car grunting, and the clown on the wall was split in half, and a path was opened in the wall.