"Sister, you've been tricked!" The masked woman heard the girl in the green shirt say the answer so quickly, and paused: "If there are ten trees side by side, two trees are empty, and there are only nine empty trees in the middle, which is actually eighteen zhang." ”

The girl in the green shirt thought about it carefully, and sure enough, it was eighteen zhang, and when she saw the playful expression on Zhang Zixing's face, she couldn't help but be furious, and she was about to pounce: "What a thief, you dare to design to deceive me!"

"Didn't the girl say that this is a child's question? Why did you answer it wrong? Arithmetic is a problem, it originally requires whimsy, so how can you tell people to say it?" Zhang Zixing laughed and said: "Everything is to convince people with reason, and since the girl has already miscalculated, could it be that she still uses force to make me submit?"

The masked woman knew that it was her own fault, and hurriedly dissuaded: "Sister, slow down! He is right, arithmetic requires strange thinking, please sister step down first, I will ask this gentleman for advice." ”

"Sister, look at his self-righteous appearance, help me teach him a good lesson!" The girl in the green shirt was convinced by this sister, and returned to the masked woman as she said.

The masked woman said to Zhang Zixing: "This lord, the set of strange books in this store was originally booked by the little woman, just saw that you stumped the sister, must be good at arithmetic, the little woman also has a question, if you can answer, I will let the sister-in-law apologize to you, and the "Heavenly Calculation" together with the "Great Business Rites" and "The Book of Herbs" a total of three sets, all given to you;

Zhang Zixing saw from the masked woman's quick answer to the question of the ten trees that she must also be an arithmetic enthusiast, and when she heard this proposal, she immediately became interested: "This is very good, it can end up in harmony, and it can also be a friend with 'calculation', please ask the young lady to ask the question." ”

Seeing his confident appearance, the woman's eyes flashed, and she said: "Today there are rabbits in the same cage, with thirty-five heads on the top and ninety-four feet on the bottom.

The meaning of these four sentences is that there are a number of chickens and rabbits in the same cage, and there are thirty-five heads from above, and ninety-four legs from the bottom, and there are several chickens and rabbits in each cage.

When Zhang Zixing heard this question, he couldn't help but smile in his eyes. It turned out that this was exactly a difficult problem that he had no answer in "Heavenly Calculation", the original question came from "Sun Tzu's Calculation", which was indeed quite difficult for the Shang Dynasty people who had just popularized mathematics.

"The conditions for this question sound too little, and it is really not easy to answer," Zhang Zixing pondered for a while, first deliberately emphasizing the difficulty, and then changed the conversation: "It's just that I just said that arithmetic requires curiosity, if you consider it from another angle, there are at least two solutions to this problem." ”

"Two kinds!" The woman's surprise was not trivial, she had thought hard and meditated for a long time and said that she couldn't solve this problem, but she couldn't imagine that this bullying aristocratic young man could actually solve it, and there was more than one way: "Please give me advice!"

The masked woman even changed her name in her heart, and the girl in the green shirt stared at her with round apricot eyes, and she had the appearance of "If you can't answer, you want to look good", the "aristocratic young man" smiled even more on his face, and slowly said the correct answer.

It turned out that Sun Tzu put forward a bold idea to solve this problem. He assumed that if half of the feet of each chicken and rabbit were cut off, each chicken would become a "one-legged chicken" and each rabbit would become a "two-legged rabbit". In this way, the number of feet of the "one-legged chicken" and the "two-legged rabbit" has changed from 94 to 47, and the ratio of the number of heads to the number of feet of each "chicken" has become 1:1, and the ratio of the number of heads to the number of feet of each "rabbit" has become 1:2. It can be seen that if there is a "two-legged rabbit", the number of feet will be more than the number of heads1. Therefore, the difference between the number of feet of the "one-legged chicken" and the "two-legged rabbit" and the number of their heads is the number of rabbits, i.e., 47-35 = 12 (birds), and the number of chickens is: 35-12 = 23 (birds).

The people on the side have a limited level of mathematics, and they can listen to it like falling into the fog, the masked woman is obviously an expert, and after listening to a few words, her eyes became solemn, and she listened carefully to Zhang Zixing's entire solution process, for fear of missing a word, gradually, her eyes have changed from initial doubt to sudden realization, and finally to excitement and excitement.

"I didn't expect that there was such a hypothetical method, the way of arithmetic, and it needed to be wonderful. Mr. has extraordinary wisdom, and now he will solve the problems in the little woman's heart, which has opened my eyes, and I hope that Mr. will forgive me for the offense. ”

The girl in the green shirt was surprised when she heard that this "thief" had really answered her sister's question, and Zhang Zixing smiled at the girl in the green shirt: "I am in the first place in today's matter, and I don't need you to apologize, so let's stop it." ”

The girl in the green shirt turned her head with a "hum", as if she didn't appreciate it, the masked woman didn't expect that her incomprehensible problem would be solved by him "easily", she admired Zhang Zixing very much, and respectfully saluted: "May I ask the gentleman's name? Where is the house? The little woman can also ask for advice or two." ”

Most of the women in this era are husbands and children, even those who like bow horses like Huang Feiyan are aliens, not to mention that masked women are so diligent and studious. Zhang Zixing also admired the masked woman: "Don't dare to be it, Miss has won the award." In Xia Zixing, he is an idle person, calling himself a free and loose person, usually living in a fixed place, only these two family members are waiting for him, and the saying of the suitable mansion and the small house is purely a joke, which makes the young lady laugh. ”

The masked woman saw that Zhang Zixing was by no means an ordinary person, and knew that this must be a lie, so she didn't break it, and continued to ask: "Mr. Shicai said that there is a solution to this problem...... The little woman is bold, please don't hesitate to tell me. ”

"This ...... It's not within our gambling agreement," the "loose people" deliberately showed embarrassment: "If the young lady is willing to agree to me, I am willing to tell you everything." ”

"The little woman also knows the secret truth...... "The masked woman frowned and said, "Sir, please tell me what the conditions are." ”

Zhang Zixing originally wanted her to take off the veil and see the true face of Lushan, but after thinking about it, she changed her words and said: "Actually, this is not a special condition, just because the method is very novel, and it cannot be explained in a few words. ”

"I'm ashamed to say that the little girl often goes to the Wei Cao Tang to teach arithmetic, and if you have time in the future, you can go there to find me. After the woman finished speaking, she took three "treasure books" from the shopkeeper and offered them to Zhang Zixing with both hands: "I hope that Mr. can give more advice to the poor students in the cottage at that time, and the little woman has thanked her in advance." ”

Send me the original author?Zhang Zixing secretly smiled and pushed the book back: "Since the date of the reunion has been set, this book will be sent to the young lady, and it will not be too late to return it to me when we meet next time." ”

The woman didn't say goodbye, took the book, and her eyes swept his face quickly, saluted and said goodbye, and left with the girl in the green shirt.

"Your Majesty, do you have a crush on these two women? Do you want to go down to find out the details of them?" Fei Zhong observed the words and saw that the Son of Heaven had other intentions, so he reluctantly came to Zhang Zixing's side and asked in a low voice. This guy's heart is clear, once these two women are lucky enough to be favored by the Son of Heaven, then his plan for today's trip will be in vain.

"No need, I have my own plans, you have a lot of rest, let's go back first, and treat the two of you. Zhang Zixing shook his head and said, which immediately made Fei Zhong and Jiang Wenhuan grateful. In fact, he did have some interest in this masked woman, but it was more of curiosity, as for the trick of "borrowing books", it was the most common move used by Zhang Zixing when he met female classmates when he was a student, although it was very old-fashioned, but it was very effective.

Back in the palace, Zhang Zixing urgently announced that the imperial doctor would treat Jiang and Fei, Fei Zhong only had a fracture, but Jiang Wenhuan's face was not lightly injured, in addition to the bruised and swollen external injury, there was also a serious bone crack. The emerald shirt beauty shot like electricity, saying that Jiang Wenhuan himself, even the bystander Zhang Zixing couldn't see what the secret weapon was, but found some strange spar fragments underground. Fortunately, with the advent of the "Hundred Herbs Sutra", the medical skills of the Taiyi have also made great progress, and the injuries of the two have been quickly and effectively treated.

That night, Zhang Zixing read the original work of "Romance of the Gods" in his super brain again, and suddenly remembered one person: Absolutely beautiful, hidden weapon, five-light stone, could it be her? I always wanted to meet her, but I didn't expect to pass by today. In the original book, this beautiful woman had a tragic fate, and after being forced to marry by an ugly man, she died on the battlefield. Now that he is the king of the Emperor, he will definitely try to prevent the beautiful woman from falling into the clutches of the "beast" - although it is common for women to marry at the age of thirteen or fourteen in this era, but in the eyes of his "modern person", he is still too young, and in a few years, he will simply make her a concubine and summon her to the palace.

As for the identity of the masked woman, Zhang Zixing was puzzled, judging from the information provided by Fei Zhong, Deng Chanyu did not have a sister, and there was no such strange woman in the original book who did not show her true face? But thinking about being able to go to that grass hall to meet her again in a few days, Zhang Zixing couldn't help but feel relieved: I don't know how beautiful this woman's true face is, if the opportunity is right, simply join the harem with this masked woman and join the "Shuangxiu Army......

Thinking of this, he suddenly became vigilant: Why has he become more and more difficult to restrain himself from a different surname recently? The desire for beautiful women seems to be stronger than before, and Yu Aiyu is also more eager to do so, could it be that the Yellow Emperor [***] has cultivated to a certain extent? It is worthy of being the favorite of perverts......

In Zhang Zixing's heart, he suddenly heard that Taishi asked to see him, and reported the urgent military situation from Jiang Huanchu, the Marquis of Dongbo--Dongyi tribe invaded.