A famous company interview question – let’s see who can answer it
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There are 50 people in the farmer’s village, and each family has a poultry bird. One day, the farmer returned and learned that some poultry in the village had contracted an infectious disease. Villagers need to check on their poultry once a day, but each person can only see whether the 49 birds of other people are sick, without being able to see their own birds. When it is determined that the poultry in one’s own household is sick, it is necessary to shoot the sick birds in order to ensure the survival of the poultry in the entire village, but each person is only allowed to shoot the poultry belonging to their own household. On the first day, there were no gunshots from the farmer ； The next day, there was still no gunfire. On the third day, gunshots were heard. At this time, the farmer learned how many sick poultry there were in the village. Excuse me, do you know how many there are? A .1 B .2 C .3 D .50
Solution process: If there is only 1 animal, then the owner of that poultry would realize that their pet is sick on the first day, upon seeing that the other 49 dogs are not sick, so a gunshot would be heard on that day. If 2 birds are sick, with owners A and B respectively, and no gunshots are heard on the first day, then on the second day A will think as follows: If my birds are not sick, then all 49 birds that B saw yesterday must have been healthy dogs; in that case, B would realize that his own birds are sick and would shoot. Why didn’t he shoot? This shows that he saw my poultry were sick. So A will shoot the next day. Of course, by the same logic, B will also shoot on the second day. In reality, gunshots were heard on the third day; therefore, using the reasoning above, there must be 3 sick dogs.
This seems to be the same as the one where people dance after turning off the lights.
Choose D: execute them all, because it’s contagious.
There are 50 people in the village, and each person has a dog. Among these 50 dogs, there are sick dogs (this disease is not contagious). So people have to find the sick dog. Everyone can observe the other 49 dogs to determine whether they are sick, but they cannot look at their own dog. The results obtained from the observation must not be shared, nor should the owner of the sick dog be informed. Once the owner determines that his own dog is sick, he must shoot it; moreover, each person has the right only to shoot their own dog, and not the dogs of others. There were no gunshots on the first day or the second day. On the third day, gunshots were heard; they asked how many sick dogs there were OP, the question should be like this
Hehe, with infectious diseases, it’s impossible to tell after just 3 days; all we can know is that in the end they will all die
Haha, it’s very simple: there are as many as the number of guns. Of course it’s C! There are many such questions online.