duration is not related here to number of lines your code have, but to number of loops it does.

However, the standard does not specify how long that "time unit" is.

Also if you have trouble discerning if the particular sequence of 1's is a dot or a dash, assume it's a dot.

Because of that.

Website support it. There is no need fix. You need to make better solution.

In the description:

Find the cheapest accommodation for student's vacation.

So, in 5 consecutive days, you can get the cheapest accommodation of [5,4,3,2,1] = 15.