Hahahaha, 1 hour for me would be a dream. Im spending already 4 and still nothing but a double loop that pass the tests, but doesnt pass the last one due to performance.

How? I wanna cry.

To take the previous population into account. Think of it as p0 + (p0 * percent / 100)

Yep, definitely.

How is it incorrect?

No, it only returns True if cnt == 0, which means you have to close all opening ones.

Everybody knows that.

Because it looks like we are pros I think =))

Thanks for your help.

That's a lot of brains.

I am an expert from now.

From what I can see, .begin() is before the 1st element and .end() is after the last element. Is that right?

Why?

Almost a year later, still the same issue.