Project Euler Forum

As a physicist I feel obliged to suggest that you add a disclaimer that your machine is not like a real-life machine, in that it will keep drilling to a preselected depth even if it were to hit water. That had me confused for a while...

Does it also take $d$ time to pull the drill back up? Or can we just begin drilling once we have the result of our previous drill?

ConnorColombe wrote: Mon Jul 29, 2024 1:04 am Does it also take $d$ time to pull the drill back up? Or can we just begin drilling once we have the result of our previous drill?

It takes no time to pull the drill back up. You can begin the next drilling immediately after the previous drilling has finished.

Problem 901 (View Problem)

I feel like the setup would be a lot clearer if instead of drilling, we were to send one-way disposable probes that take $d$ cost to survive up to $d$ depth

It confuses me that the "groundwater depth is constant in the relevant area".

If all drilling locations are chosen in the same "relevant area" this conflicts with the groundwater depth being a random variable.

If not, what does the "relevant area" mean in this context?

Thanks for any help

The depth of the groundwater is random, that means, you don't know it, before you find it.
But at each try for a drill, this unknown depth is the same.