If you're looking for NodeJS built-in modules, then take a look at NodeJS v18 API docs

Here: https://docs.codewars.com/languages/javascript#node-modules

A typo happens when you want to write something and write something else instead, in this case, strng is the intended value, so no, it's not a typo.

No it's not. It's a var name.

Note that you can start at first or second step. Likewise you can end at last or second to last step. In the order given in the description:

climbing_stairs([0, 2, 2, 1]) ➞ 2

The cheapest route is the first (index-0) and third step (index-2). So 0 + 2 = 2.

An alternative route is the second (index-1) and third step (index-2). So 2 + 2 = 4, but that is more expensive than the first route.

Another alternative route is the second (index-1) and fourth step (index-3). So 2 + 1 = 3, but that is also more expensive than the first route.

climbing_stairs([0, 2, 3, 2]) ➞ 3

The cheapest route is the first (index-0) and third step (index-2). So 0 + 3 = 3.

climbing_stairs([10, 15, 20]) ➞ 15

The cheapest route is the second step (index-1). So the cost is just 15.

climbing_stairs([0, 0, 0, 0, 0, 0]) ➞ 0

Here the cheapest route is any legal route as all "jumps" are free.

the image is stored on a Russian server; your country may be blocking Russian websites

I do, it's a man laying unconscious at the beach holding a barrel in its arm. Maybe you're blocking the image host or something?