ELI5: Explain Like I'm 5

Water pouring puzzle

Alright kiddo, imagine you have a big bucket full of water and you want to pour it in three smaller cups, but each cup has a different size and shape. But, here's the catch, you can only use the big bucket to pour the water and you have to fill each cup to the top without wasting a single drop.

This is called a "water pouring puzzle". It's like a game where you have to use your thinking brain to solve a problem. You need to figure out how to get the water from the big bucket into the three cups without spilling any water.

Now, let's say that the big bucket can hold 9 cups of water, and the three small cups have different sizes: the first one can hold 4 cups, the second can hold 5 cups, and the last one can hold 3 cups.

So, if you pour the water randomly, you might end up with some cups overflowing and some others still empty. But don't worry, there is a solution! You just need to pour the water in a special way.

First, pour water into the 5-cup cup until it's full. Then, pour the water from the 5-cup cup into the 4-cup cup. This will leave 1 cup of water in the 5-cup cup.

Next, pour the water from the 4-cup cup back into the big bucket. Then pour the remaining 1 cup of water from the 5-cup cup into the 4-cup cup. Finally, fill up the 3-cup cup from the big bucket, which should leave you with exactly 2 cups of water in the big bucket.

Now you have filled all the cups without wasting any water! Congratulations, you solved the water pouring puzzle!
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