ELI5: Explain Like I'm 5

Asymptotic computational complexity

Asymptotic computational complexity is like trying to figure out how long it will take to do something really hard, like sorting a big pile of toys. You know that the time it takes to do it will depend on how many toys there are, and how fast you can sort them.

Imagine you are trying to sort a pile of toys into buckets by color. Let's say you have ten toys, and it takes you five minutes to sort them. Now imagine you have a hundred toys. It will take you longer, but how much longer?

This is where asymptotic computational complexity comes in. It's a fancy way of saying that the time it takes to do something complicated can be described by a formula that tells you how much longer it will take as the problem gets bigger.

In our toy sorting example, we might say that the time it takes to sort N toys is proportional to N^2. That means that if it took you 5 minutes to sort 10 toys, it would take you 100 minutes to sort 100 toys.

But wait, there's more! Different sorting algorithms (ways of sorting the toys) can have different asymptotic computational complexities. So even though they both might take longer as the number of toys increases, one might be faster than the other.

So, in summary, asymptotic computational complexity is a way of figuring out how long it will take to do something really hard, like sorting a big pile of toys, as the problem gets bigger. It helps us compare different algorithms and figure out which one will be faster for a given problem size.
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