Zhang Huan left, but Li Yi fell into deep thought, and after a while, he took a piece of wood from the side to write and paint. He struggled to write, apparently not yet accustomed to this so-called pen and paper.

Although paper already existed in this era, it was very unfortunate that this paper was constantly of poor quality and expensive. At least, it is not something that Li Yi can consume. Of course, there are some on Huangfu Gui and Zhang Huan's side, but in their opinion, it is better to write on that kind of paper than on wooden tablets or wooden slips.

The so-called wooden tablets and wooden tablets are actually wood cut into thin slices, and the wooden tablets will be made one by one, and then they will become a common book in this era, also called Jian Ce. The wooden slip is an enlarged version of the wooden tablet, but it is generally only used to write words such as announcements or contracts with a small number of words.

This kind of extremely inconvenient pen and paper made Li Yi extremely awkward in the process of writing, and the words that were already very scummy in his previous life became even more scummy. It's a pity that Huangfu Gui didn't think it was a strange thing to have ugly words at all. As he himself said, if Li Yi's handwriting is very beautiful, then he really doesn't know if he is still qualified to be Li Yi's master.

After a long while, Li Yi finished writing the painting, picked it up and looked left and right, and couldn't help but show a hint of a wicked smile, "I don't know what kind of expressions the two masters will show after seeing this?" ”

In the time-traveling novels I read in my previous life, the protagonist always made all kinds of inventions as soon as he crossed over, as if everyone was an expert in mathematics, physics and chemistry, and he was the kind with top theory and practice. But Li Yi is not so awesome, an ordinary person in his previous life, where did he know what glass, gunpowder, and papermaking skills? But now, he's finally found his chance!

Yes, it's just that you have found an opportunity, and you will definitely not forget it because it has been useless for too long.

A few days later, when Huangfu Gui was ready to let Li Yi know what a real master was with all kinds of problems he had prepared, he was stunned by what Li Yi had taken out.

"Master, this thing is called a simplified number by the disciple, because the disciple thinks that although the calculation is intuitive, it is not concise enough. So the disciple pondered such a simplified version of the number, which represented 0 to 9 through simple symbols. This 0 is the empty space in the calculation, and the disciple thinks that using the empty seat will easily cause mistakes......" Li Yi Balabala kept explaining.

These are all things he came up with during this time, all the advantages of Arabic numerals compared to arithmetic, and if he had this kind of energy in his previous life, he might be able to get into a good university.

At this time, Huangfu Gui had also detached himself from the shock and began to seriously study the symbol that his disciples had concocted. Although Huangfu Gui is not very proficient in arithmetic, such a thing as learning is common in many places, let alone a wise man like him.

It didn't take long for him to understand the advantages of this new type of number, and of course, he saw many disadvantages, but it was much better than the way of writing with arithmetic. At its simplest, it is easy to modify the numbers by using calculations, so many important places still use words to write numbers. But now Li Yi's figure can reduce many of these situations, although it can't be eliminated completely, but it is already very good.

"Good stuff!" Huangfu Gui touched his beard and exclaimed, "Ayi, discuss it with Ran Ming for the division, and then report it to the imperial court." ”

just said so, but Huangfu Gui didn't look as excited as Li Yi imagined, which made Li Yi feel a little strange. In fact, this is also normal, because Arabic numerals were also not taken seriously when they were introduced to China between the Song and Ming dynasties.

The reason for this is that the arithmetic itself is a very intuitive form of digital representation, and even people who have not read a book can easily distinguish it. Of course, the most important thing is that the calculation has been circulating in China for thousands of years, and at that time, the implementation of any new things was indispensable to the support of the imperial court, if the imperial court did not pay attention to it, how could it change the habits of the common people?

After all, although Huangfu Gui knows arithmetic, his real identity is a general, and going into battle to kill the enemy and defend the country is what he is most concerned about. Arithmetic? Free another group of people to study.

However, Li Yi didn't care too much about this, after all, he didn't care what the numbers used to show him, after all, he didn't plan to do anything in arithmetic. So, he quickly came up with another thing.

"This is ......" Huangfu Gui took the object and looked at it carefully, only to see that the object had a rectangular wooden frame, and in the wooden frame, small wooden sticks were fixed, and each wooden stick was wearing 6 wooden beads. At the same time, there is a horizontal wooden stick in the middle, which divides the six beads into the shape of the upper and lower five.

If any modern person sees it, he will definitely recognize this thing at a glance, abacus! An uncomplicated creation that contains the wisdom of the ancestors has now been directly concocted by Li Yi.

In history, at the end of the Yuan Dynasty and the beginning of the Ming Dynasty, the abacus was already widely used, so many people believe that the emergence of the abacus should be in the middle of the Yuan Dynasty or the Song Dynasty. However, for Li Yi, he doesn't care when the abacus appears, anyway, there is no one in this era!

Yes, when he learned from Zhang Huan that there was no abacus at all in this era, he decided to make one himself, of course, he didn't know how to work as a carpenter, but there were too many apprentices under Li Yan's command who could live like this. Although the abacus made is not very fine, it is enough for the mold to come out, because what Li Yi needs is just such a mold.

"Master, this is the disciple's research based on the calculation, and this is how it is used......" As he spoke, Li Yi directly demonstrated it to Huangfu Gui. Of course, he demonstrated only the most basic calculations, and he didn't demonstrate for long. On the one hand, because he demonstrated twice, the abacus was suddenly robbed by Huangfu Gui, and on the other hand, it was ......

Ahem, Li Yi's mastery of things like abacus is only limited to these foundations. After all, in the era of calculators, who would use an abacus?

However, even without Li Yi's demonstration, Huangfu Gui quickly mastered the use of the abacus, after all, strictly speaking, the abacus evolved from the calculation. Of course, in high-level applications, there will be many differences between using a calculation chip and using an abacus to calculate, but those things are not something that Li Yi needs to worry about. The only thing he wants to do now is to completely confirm his reputation as a prodigy! It would be better if it could be passed on to the Kyoshi.

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After my own unprofessional research, the title of father in this era should be father, which has been modified