Liu Yuan raised a finger and shook it, "No, go back in time and make big news as much as possible, I need you to change the direction of history." ”

Yang Pingfan was stunned, "Changing the trend of history, aren't you afraid that the butterfly effect will affect the baseline time and space?"

Liu Yuan laughed, "Do you remember the experience when you traveled to the Ming Dynasty with Dr. Su?"

Yang Pingfan remembered that he and Su Yu ran to the Yongle period of the Ming Dynasty by mistake and guided Zheng He's fleet to complete the feat of circumnavigating the world.

Liu Yuan continued: "You and Xiao Yu completely changed the historical trajectory of that time and space, and as a result, it had almost no impact on the baseline time and space, do you know the reason?"

Yang Pingfan nodded, "Professor Li told me that ordinary crossing is equivalent to throwing stones in the long river of history, and the splash of water is the butterfly effect. ”

Liu Yuan snapped his fingers, "That's right, that's the truth, this is actually equivalent to creating a parallel universe, so I ask you to cross over, and you must make big news." ”

Yang Pingfan's eyes lit up, "Sounds exciting enough." ”

Liu Yuan was overjoyed, "Yes, how about it?"

"Just me?"

Liu Yuan shook his head, "No, you can form a team, but the number of people can't be too many, it's best not to exceed four people, after all, you have to carry the necessary equipment and supplies, and the space of the traversal cabin is limited, so you can't bring so many people." ”

Yang Pingfan nodded, "That's okay, but I have a request, I need Dr. Su's participation, after all, her profession, I need her knowledge." ”

When Liu Yuan heard this, his face twisted, "Xiao Yu can't go with you, she...... Well, she's pregnant......"

Yang Pingfan was stunned when he heard this, and randomly punched Liu Yuan, "Okay, it seems that I will call Dr. Su's sister-in-law in the future, then I will find someone myself, which dynasty will I go to?"

"The last years of the Western Jin Dynasty!"

"Why it?" Yang Pingfan's face was full of surprise, there were so many magnificent turbulent times in thousands of years of history, but Liu Yuan chose the last years of the Western Jin Dynasty, a period that almost no one expected.

Liu Yuan turned on the holographic projection on his wrist, and the dream story that had been woven quickly flashed on it.

"Let's put it this way, among the traversers, nine out of ten are going to rebel and claim the emperor, and they have to resist foreign insults, there were originally several dynasty candidates, but considering that one is that other dynasties are playing too much, but this is an opportunity to travel through and completely distort history, so we set the time anchor a little farther, the purpose is to prevent accidents, if there is no way to produce a parallel universe, the self-correction of history can also make up for the hole that you have crossed out. ”

"Understood. ”

Liu Yuan patted Yang Pingfan's shoulder, "You select the personnel as soon as possible, and the expert team will conduct training for you on the background of the times. ”

Without Su Yu's history, after Yang Pingfan thought about it, Li Lan would definitely go with him, who would the others look for? Zhang Xiaoming's decadent face entered his mind.

——

"It's time of the year to kneel and confess to your math teacher.

I'm sorry, I didn't learn it well at the beginning, this set of questions on Double Eleven is getting more and more difficult every year, and the concubine really can't !!"

Li Lan looked at the mess of discounts on various shopping websites, and couldn't help but let out a sigh.

At the beginning, Double 11 was a pure shopping promotion festival, the whole field was 50% off, 0 point seckill, the fight is hand speed, the grab is affordable, as long as a network cable, a person can fight flexibly, play the whole individual game in one minute, and have a clean harvest year.

However, I don't know when it began, Double 11 has become a brainpower competition, or the whole of that hanging, the preferential mechanism from a simple "five fold" and "eight fold" to "full 200 minus 20", "two pieces of eight folds, three folds on the discount", and then to today's "original price of 30 yuan a box, the first 50 pieces of 85 off, after the full 250 of each piece 6 off, the prepaid deposit is doubled, and the shopping allowance is parallel discount".

It's the annual Double 11 shopping carnival again, but Li Lan finds that she really can't understand the more and more complicated discount formula, even if she uses her 985 brain, from October to November, she can't figure out how many coupons she can get, in order to buy this log thickened paper towel, she is a liberal arts student, she has a headache when she sees mathematics, and she can't learn the arrangement group on the blackboard, let alone this.

Not to mention the building game of people pulling people, annoying people, and scolding people, sixteen private message links every day to get people up, saving children on time at half past nine every night, and people in the friend group who ask to build a building can row up from Suzaku to the imperial capital, and every time they are in a hurry to think that love is knocking on the door.

Su Yu next to him looked at Li Lan who was stunned with a smile and said: "Everyone is very depressed, it's just a matter of buying something on Double 11, why do you want to make such complicated preferential rules to "test" us? Why can't you simply discount it like in the past?"

In the final analysis, tossing you and paralyzing you is not to better hollow you out, behind the many mechanisms, there are real economic principles lurking, just to better capture you. ”

Li Lan pushed the laptop away and pulled Su Yu's sleeve, "Sister Yu, you are a doctor of psychology, tell me about it." ”

Su Yu didn't answer directly, but asked: "Let me ask you a few words first, what is deposit inflation? What is parallel discount? What do red envelopes, allowances, and coupons refer to? What is the difference between deposit deduction, deposit doubling and actual deposit?"

A few more short-answer questions, does the use of this year's Double 11 allowance and coupons include a deposit? Can the pre-sale and non-pre-sale be settled together? The full discount includes a deposit, and the package does not include the deposit inflation part? Please explain in detail and explain the reasons for the above.

Finally, the finale of the application question, it is known that a store has a shopping allowance of "50 for every 400", a store coupon "20 for 469", and a member-exclusive coupon "for every 300 points for a 50 yuan coupon, full 398 to use" "every 600 points for a 100 yuan coupon, full 718 to use", of which the store coupon is a full reduction of the actual amount paid for a single order, and cannot be used with a member-exclusive coupon/ Single product coupons can be used in combination, and the coupon can be used in conjunction with coupons, but can only be used on Singles' Day.

So the question is, if Ah Hua wants to buy a black essence, the pre-sale price is 309 yuan 50ml, the deposit is 20 double expansion, the membership points are 932, and her budget is 2000 yuan, how to buy the most cost-effective?

Let's upgrade again, if you buy a wool coat from another store, the price is 899, the deposit is 50 to 100, the allowance is full and reduced across stores, and the coupon does not support parallel discounts.

Li Lan listened dumbly, Su Yu smiled and rubbed her hair, "In the face of this test paper like a book from heaven, some people gave up on the spot, clicked Buy Now to pay and finished, some people took out scratch paper and calculators, calculated ignorantly, stared at the mobile phone to grab coupons, do tasks, but they didn't know that they were walking into the 'trap' preset by the merchant step by step."

This trap is called "price discrimination", which means "discriminating" consumers with different prices and selling the exact same product or service to different buyers at different prices. The rich sell it for a little more expensive, and the poor for a little cheaper.

For merchants, they pursue the maximization of revenue, hoping to sell to everyone at the highest price, but they are not sure what the psychological budget of each consumer is, so they set up many checkpoints to let consumers expose their budget.

For the poor, they have a lower budget and are willing to pay more to get a good price, while those with a high budget are too troublesome and may buy it if they want to.

So the complex preferential rules have become a good filter, screening out the rich people with high budgets, leaving the poor people with low budgets, diligently saving coupons, building buildings, making up full reductions, receiving red envelopes, doing ninety-nine brain-burning math problems, and saving ten yuan, eight yuan and a half cup of milk tea money.

Doesn't that sound a little sad? When you roll up your sleeves and pick up wool, you're actually exposing your hole cards to the merchants.

The time of the poor is not valuable, so they can exchange their time for money. There is nothing in this world that will live, but there is really no money.

And that's not all, for the poor, the routines are interlocking.

Once you start to do this set of math problems on Double 11, you will find that the original intention of the teacher is to defeat you, and it is difficult to fail the subject.

For the poor, shopping often around for things, but when it comes to Double 11, you really can't figure out which one is the cheapest, and you can't even count how much it sells, if you still don't understand, then I'll give you an example.

Suppose you want to participate in Double 11 and are determined to buy the cheapest hairy crab flavor potato chips, the first activity is "20 yuan a box, buy one get one free", and the second store activity is "30 yuan a box, now 65% off, if you spend more than 100 yuan, you can also return another 20 yuan coupon, cross-store can be full reduction but does not support single product coupon parallel discount", what should I do?

Most people who want to take advantage of the cheap will definitely do their homework seriously and shop around, but the merchant has set up a variety of complex discount conditions in advance, and under the fancy calculation, it is about to die when it comes to the second one, and then it is calculated for an afternoon, and it is found that the fourth one is cheaper, and the agency is exhausted, or lost to the merchant.

In fact, this is a very typical "price confusion", where merchants set up very complex activities, so that consumers cannot accurately calculate the actual price of goods, so they encounter difficulties in price comparison, and then let merchants obtain excess profits.

And in the end, I compared and compared, and finally placed an order in a daze, and looked at the deduction record, hey, isn't this five yuan cheaper than the original price? Just like the last big question of mathematics in the college entrance examination, the operation is as fierce as a tiger, and the score is 55, who can blame this? Of course, the teacher who is to blame for the question. ”