315.

When it comes to learning, there are usually two rates of time flow.

One is to learn boring knowledge that you are not interested in, and that time is like a year.

The other is in the case of spontaneous interest, where the learning time passes quickly.

So, when everyone felt that there was still some unfinished business, this two-hour lesson was quickly finished.

Originally, Cheng Li thought that he could end his first day of class like this, but he didn't want to have a little episode when he was about to announce the end of class.

That is, Cheng Li saw that the old man raised his right hand high.

"Old, what's the problem?"

The old man then stood up and asked, "Master Cheng, may I ask if this course will really be called 'arithmetic' in the future?"

"This ...... I can't say that I can't change it, what's the problem?" Cheng Li wondered.

After considering the words, the old man said, "That's the case, count...... In fact, this word has already had a use on Qingling Island. ”

"Oh, what did you do with the word count?"

"Arithmetic is used on Qingling Island to ...... Calling children for initiation arithmetic ......"

Cheng Li understood when he heard this.

"Oh, it turns out that your Qingling Island has turned enlightenment arithmetic education into arithmetic. ”

Cheng Li didn't expect this, he was originally a bitter hand in choosing a name, so Cheng Li simply combined arithmetic and mathematics with 'calculation' and 'number'.

However, since Qingling Island already has a name for arithmetic, it is a bit inappropriate to call this new discipline arithmetic at this time.

"Well, that doesn't mean arithmetic, then...... Do you have any good name suggestions?" asked Cheng Li.

The old man pondered for a while, as if he had already thought of a name.

"I have a name for this, and it's called 'Arithmetic'...... How?"

"Reckoning?"

"That's right, in the sense of entering the Tao. ”

"Well, that's a good name, I'm okay, what about you?"

Everyone nodded one after another, and they all said that the name of arithmetic is much better than arithmetic, and it seems that these people also felt that arithmetic, which was originally called the name of enlightenment teaching, was used to refer to the new discipline, which seemed a little disobedient, but they didn't have the courage to put it forward as old, and now they all agreed with it.

"Okay, then this new discipline that integrates arithmetic and mathematics is called arithmetic!

"May one day we all be counted into the Tao!"

......

In this way, Cheng Li's first day of lecture tour came to an end.

After leaving Qingling University, Cheng Li came to a place 12 miles west of Tongling Peak non-stop.

It is very famous on Qingling Island, and it is also a crucial point in the battle a few days ago.

That is the location of the Sword Cliff on Qingling Island.

Cheng Li stood at the bottom of this cliff that seemed to be vertically split by a sharp sword, looking up at the nearly thousand-meter-high sword cliff, and couldn't help but feel a little surging for a while.

At this time eight days ago, Cheng Li came out of the spirit prison at that time, and was entrusted by the great elder to come to the Sword Cliff to enter the Yin and Yang Secret Realm.

Recalling it at this time, Cheng Li felt that his blood was surging, as if he had returned to the extremely fierce battlefield at that time.

"It's been eight days before I know it, and I don't know how Xiao Hei is?"

After the end of the war, Cheng Li experienced a series of intensive and tedious things such as retreat, optimizing exercises, studying spells, and conceiving the development plan of Qingling Island, so Cheng Li never had time to return to the Yin and Yang Secret Realm to fulfill his promise to Xiao Hei.

At that time, in the secret realm of yin and yang, he was also saved by Xiao Hei, and Guiyuan Zhenren once left a will, hoping that he could take care of Xiao Hei.

And Cheng Li also promised Xiao Hei to take him out and see the outside world.

Cheng Li has never forgotten this matter.

So at this time, after the things at hand were finally done, he came to this sword cliff for the first time, ready to enter the Yin and Yang secret realm again.

"See Master Cheng!"

Cheng Li didn't stand under this sword cliff for long, and immediately two people walked out of the path on the side of the sword cliff and saluted Cheng Li respectfully.

"No need to be polite, I want to go to the Yin and Yang Secret Realm. Cheng Li waved his hand.

"Okay Master Cheng, it just so happens that the entrance to the Yin and Yang Secret Realm has just stabilized this morning, and now you can enter at any time!"

So, under the leadership of these two people, Cheng Li came all the way to the top of the Sword Cliff.

In the previous battle, the Five Elements Lock Pass Array, which guarded the entrance of the Yin and Yang Secret Realm, dissipated with a bang along with the Island Protection Array under the final layout of Tuomu Zhenren.

After losing the Great Array of Five Elements Locks, the entrance to the Yin and Yang Secret Realm was on the verge of being disconnected for a while.

However, fortunately, during Cheng Li's retreat, the old man and others arranged manpower in time to rearrange the entrance of the Yin and Yang Secret Realm and stabilize it.

The difficulty of such a formation is not small, and with the concerted efforts of all the remaining people in the Formation Mansion, it took eight days to finally stabilize the entrance of the Yin and Yang Secret Realm again.

Cheng Li came to the top of the Sword Cliff and saw that a pavilion had been built, and the pavilion was covered with mysterious formations.

In the middle of the pavilion, there was a teleportation of light that was slowly rotating very steadily.

"Huh, has the entrance of the Yin-Yang Secret Realm been moved to the top of the Sword Cliff? I remember that the entrance to the Yin-Yang Secret Realm was in a cave in the belly of the Sword Cliff. ”

A leader next to him immediately replied: "The previous entrance to the Yin and Yang Secret Realm is no longer usable due to the disappearance of the Five Elements Lock Array. So now that the formation was re-arranged, the entrance was moved to the top of the Sword Cliff. ”

Another person also chimed in: "A thousand years ago, in order to hide the Yin and Yang Secret Realm from being destroyed by the gangsters, Guiyuan Zhenren deliberately set the entrance of the Yin and Yang Secret Realm so hidden. And now that the war is over, we have also regained the inheritance of yin-yang arithmetic under the wisdom and martial arts of the head of Cheng, so we simply set the entrance of the Yin-Yang Secret Realm at the top of this sword cliff, which is the place where the aura gathers, and it can also make the entrance of the Yin-Yang Secret Realm more stable. ”

Cheng Li nodded and said, "I see, then for the follow-up development of the Yin and Yang Secret Realm, will the elders have a plan?"

The two looked at each other and said, "Not yet, the entrance to the Yin-Yang Secret Realm has just stabilized today, in fact, we have only just sent 3 teams of people in to check the situation of the Yin-Yang Secret Realm."

"Master Cheng, as you know, the Yin and Yang Secret Realm was on the verge of being half-destroyed in the Great War a thousand years ago, and it was full of traps and crises, so if you don't investigate the situation inside, you can't enter it on a large scale and reuse this secret realm. ”

"Yes, according to the report of the personnel who entered the third team, there is also a giant snake in the Yin and Yang Secret Realm, which is extremely ferocious, and after injuring one of us, it will immediately hide, which is very cunning!"

"Well, we're planning to organize a fourth investigation team to hunt for them!"