Quiz: Only very high IQs can save these pitiful creatures from the forest fire

It has been a long time since "brain training", then today let's go back to the classic river puzzle but at a higher level.

Here is the situation for you:

One day, there was a fire on the far-away meadow. At first it was small, but then the fire spread and spread, causing the entire grass to burn. Eventually, only 6 creatures survived and were trying to escape the fire: 3 lions and 3 antelope.

On the way, they hit a river full of hungry crocodiles waiting below. To escape, the animals were forced to cross the left bank of the river without being able to swim, and fortunately there was a raft nearby.

Now suppose that these poor creatures also have a bit of our wisdom. They can fly, but the raft can only carry up to two animals, whether the same or different species. And of course always need at least one animal on the raft to paddle across the river.

The problem now is troublesome: if on one of the river banks, the number of lions is bigger than the antelopes, instinctively, the lion will eat the antelope immediately. This condition applies even when friends dock. For example: a lion carrying a lion and an antelope, but a lion is available on the shore, and immediately upon landing, the antelope will be eaten.

And remember, any way that is not the fastest will cause these pitiful creatures to die.

Try to think for yourself before looking at the solution below.

Summarize the topic:

There are 6 animals: 3 lions, 3 antelopes; and 1 wooden raft.

Find the fastest way to get 6 creatures across the river, knowing that:

1. The raft can only carry 2 animals at the same time.
2. Always make sure the number of antelope is more than the lion, otherwise the lion will eat the antelope.
3. Any way that is not the fastest will cause them to die

Answers:

To solve this kind of puzzle, we need to list all possible decisions in a situation, and every outcome that each decision leads to.

For example, in the first river crossing, 5 decisions can be made: putting up 1 antelope, 1 lion, 2 antelopes, 2 lions, or one animal.

But here, only 2 options are possible: give 2 lions, or give 1 lion, 1 antelope. Because if you put 2 antelope across the river, the remaining uncle will be eaten again. If you leave a raft antelope, the other two are . determined.

If you leave me .

Now try with the option to bring 2 other animals.

Hit 1: lion + antelope

When we reach the other side, we have to calculate who stays. If you leave the antelope, the lion returns, so the other side immediately has 3 users, which is not feasible.

So the lion must stay and the antelope returns.

Turn 2: the antelope returns, the lion stays

Here, we have a number of options, but it should be noted that the left bank has a waiting lion available.

If you leave 2 antelope on a raft across a river, the lonely person will never go back. This time, it is impossible to carry both antelopes and lions, because the left bank lions will excel right away.

So this time, there is only one "dull": 2 historians cross the river.

Hit 3: lion + lion

Next, one uncle went back to the rafting raft, leaving two fellow on the left bank.

Turn 4: Lion returns

Now what to do? In fact, the only option is to have 2 antelope on the raft along the river.

Hit 5: antelope + antelope

Our situation now is as follows: The left bank is now balanced by 2 lions and 2 antelopes. So is the right bank: the score is 1-1.

But now it is impossible to return the antelope, because it will succeed. It is also impossible for a lion to come back, just dock, the other antelope will be eaten again.

So on the raft back, there is a 1 antelope and 1 lion.

Turn 6: antelope + lion returns

What now? Simply put, leave the lion to the right bank, 2 antelopes to go to the left bank. This is the only way to help the antelope exceed the lion.

Hit 7: antelope + antelope

Now, you can breathe when the antelope has gathered enough of the left bank to stay safe before the lion.

Left, just need a lion rowing raft to turn each of his fellow species through the river is finished.

So a total of 11 moves and still the smallest number. Do you have any shorter way? Please share it.