An interesting puzzle question, if you are interested, please do it. Tell me why

It's June 4th.

Xiao Ming's first sentence excludes the possibility of June 7 and December 2, because both 7 and 2 occur only once in the n-value.

After excluding these two dates, only the month of June 4 did not repeat.

That's why the two of them can guess.

September 1st, which my dad calculated, and I calculated it was June 7th, which later turned out to be wrong.

Kao's head is so big that his mind should have rested. It's September 1st. The King of the Sea made it clear.

The answer is: September 1.

1.Xiao Ming said: "If I don't know, Xiao Qiang definitely doesn't know."

The subtext of this sentence is actually: "I should have guessed correctly, if I guessed wrong, Xiaoqiang definitely didn't know". But Xiao Ming is still not sure whether he guessed correctly or not, and Xiao Qiang needs to confirm it.

What value does m take to make Xiao Ming say that? Obviously, 6 and 12 are not advisable, if M is 6 or 12, N may be 2 or 7 - Xiaoqiang can know Mr. Zhang's birthday with a number of 2 or 7. m can only be 3 or 9, and n can only be taken in .

If m is 3, n can take three values, and the result is "If Xiao Ming doesn't know, Xiao Qiang may know (2 4, 3 8), or he may not know (3 5)." In this case, Xiao Ming's statement that "if I don't know, Xiao Qiang definitely doesn't know" is not in line with the facts, and Xiao Ming is not enough to say so confidently.

If m is 9, then Ming knows that n can only be 1 or 5. At this time, Xiao Ming's guess is n=1, and whether n is 1 or not, Xiao Ming is not sure, if n is not 1 but 5, then Xiao Ming said "If I don't know, Xiao Qiang definitely doesn't know". At this point, in fact, Xiao Ming already knows, and there are only two situations, just waiting for Xiao Qiang to confirm whether n is 5.

2.Xiaoqiang said: "I didn't know it at first, but now I know."

Xiaoqiang said, "I didn't know about it originally", verifying that n is indeed not 2 or 7; At the same time, Xiaoqiang also knew that "M is not 6 or 12, M only has 3 and 9 to be preferable". If n is 5, then Xiaoqiang should say "I didn't know it originally, but I still don't know it now". According to the inference of the first section, n = 1, so Xiaoqiang can say "I didn't know it at first, but now I know".

3.Xiao Ming said: "Then I know too".

Xiao Ming is waiting for Xiao Qiang's words, no matter what Xiao Qiang does, Xiao Ming will know the correct answer. If Xiao Qiang says "I still don't know", then Xiao Ming can still know that "only n=5 will make Xiao Qiang at a loss", so the answer is September 5; If Xiaoqiang says "I know", then it must be September 1.

In fact, from beginning to end, Xiao Ming understood, he only needed Xiao Qiang to say Juhua to verify his guess, for Xiao Ming, it was a multiple-choice question of either A or B. Therefore, according to the story development clue of the topic itself, Xiao Ming's third sentence can be omitted, but many people use this condition when deriving - that is a bit like doing a math problem.

September 1. Because Xiao Ming dares to say the first sentence, it means that the month he knows is definitely not 6 and 12, because if the month is one of 6 and 12, Xiao Qiang has the possibility of knowing the birthday, because 7 and 2 only appear once in these two months, and from the second sentence, I know that the day is definitely not 5, because in March and September, 5 appears twice, if it is 5, Xiao Qiang is still uncertain, so the day can only be, the third sentence tells us that it is not March, because if it is March, Xiao Ming can't be sure when it is his birthday, So it can only be the September issue.

June 4th. Xiao Ming said: If I don't know, Xiao Qiang definitely doesn't know that there must be a repetition of the month, Xiao Qiang said: I didn't know at first, but now I know that the date of the note is repeated, so you can remove June 7 and December 2.

After the removal, the only thing that did not repeat the month was June 4th.

Support the King of the Sea on September 1.

June 7. Because the easiest way, because the condition given is that if you don't know m, you don't know n, then you can be sure that there are two months in the group, and you can exclude March and December; If you know n, you know m, and you know that n must not be repeated in these dates

The King of the Sea is correct, it should be September 1st, support!

The easiest way, because the condition given is that if you don't know m, you don't know n, then you can be sure that there are two months in the group, and you can exclude March and December; If we know n, we know that m knows that n must not be repeated in these dates, only June 7.

Agreed June 7th

I think so, it's unlikely that there will be three times in March and September, right?

June 7. If the teacher tells him that it is March, September, or December, then Ming will not know which day it is, because if Ming only knows one of the months, he will most likely guess the date of any of the months. But Xiaoqiang said that he didn't know about it, but now he knows because nothing else is possible, only in June.

Because if it's the 7th, one is because there is no other date on the 7th, since Xiao Qiang knows, then Xiao Ming naturally knows, Xiao Ming knows that the value given to Xiao Qiang by the teacher can't be the 4th, because there is a 4th in March, so it must be the 7th, and the answer is June 7th. Some people will say, why can't it be December 2nd, you see, if Xiao Ming only knows that it is December, can he be sure what day it is in December? So where will you put it on June 7th?

Since he had doubts on December 2nd, he would definitely not choose this, but would definitely be June 7th.

June 7. Because both of them looked at the ten sets of numbers above, Xiao Ming said I don't know, he didn't know, it means that Xiao Ming didn't know, Xiao Ming said I know now, he said he knew (only 7 in the ten groups of numbers is alone), so he can say it. Xiao Ming said that I also know, which means that Xiao Qiang doesn't know the situation in the month and doesn't know how many days it is, but it's only June 7.

According to. Xiao Ming said: If I didn't know, Xiao Qiang definitely didn't know Xiao Qiang said: I didn't know either, but now I know.

Xiao Ming said: Oh, then I know too.

Get n without repeating.

So the final answer was June 7, n did not repeat.

September 1. Xiao Ming can be sure that Xiao Qiang can't guess, which means that Xiao Ming knows that it is not June 7 or December 2, because Xiao Qiang can only know if he masters the last 7 or 2. And at least Xiao Ming knew that it was not June or December, and he hinted at Xiao Qiang when he said this.

There are only 3 months and 9 months left, and if Xiaoqiang has 5, he still doesn't know, and at this time it can only be 1 4 8 No matter which one he can accurately say the teacher's birthday. This.

At this time, if the teacher's birthday is March, Xiao Ming naturally still doesn't know. He must have known that it would be September. So the teacher's birthday is September 1st.

A farmer crosses the river with a dog, a rabbit, and a cabbage, and there is only one small boat, and every time the farmer crosses the river by boat, he can bring one item with him, and when the farmer is not there, the dog eats the rabbit. How can a farmer cross the river with all his stuff?

I'll just give you a question, it's a bit difficult. 12 balls, one of which has a different mass from the other balls (I don't know if it is medium or light), use a day to find the ball, weigh 3 times.