That Nim Flashbacks

I like recursive functions tho

Yet I have not met a CS grad without a trauma.
- I've had 7 traumas this week and counting rocks back and forth
- I have a production bug... it only happens on Saturdays ever our ops folks have no idea - this can be replicated on a test server that gets no traffic.
  Saturday why!
I've always hated recursion. It's always seemed like a cutesy programming trick that's not reliable in all conditions.
You could blow the stack in an edge case that you didn't think of. So it should never be a standard pattern. It's only good if you need to rewrite something for optimization and recursion is appropriate. But in many cases recursion is slower.
"Look at what I can do in 5 lines of code!" is for programming contests, not for anything important.

Nah Hanoi was easy stuff, first year. Definitely more traumatizing practice problems.

Hanoi […] practice problems.
Like you come to the exam and there's a 64 piece Tower of Hanoi you need to solve manually to pass the exam
- Assuming 1 second per swap, a 64 disk tower of hanoi would take 585 billion years to solve - it has 2^64 -1 swaps.
- Calm down, satan
Yea, get back to me when you get to parallel programming.
- Or even just try to understand pthreads.
- Writing kernels for parallel execution with OPENCL gives me flashbacks every time I remember them
- Tis' not hard, just add some sleeps to make sure other thread reads data before it is destroyed 🌚

I didn't have to program this, thankfully. The code was used as an example of recursion but the explanation was lacking so I ended up writing out each frame by end until I understood it. Took a few pages and a couple of hours.

I am grateful that I learned what I did going through it but I'd rather not do it again.

Fuck all programming puzzles. I refuse them.

True hommies hate them too.

Replacing "Programmers:" with "Program:" is more accurate.

It'd be a trick if you didn't already know the answer. Or at least, it would be for me. It's also hard to actually visualise.
- I didn't know the answer either, but usually you can compose solution from solutions of smaller problems.
  solution(0): There are no disks. Nothing to do. solution(n): Let's see if I can use solution(n-1) here. I'll use solution(n-1) to move all but last disk A->B, just need to rename the pins. Then move the largest disk A->C. Then use solution(n-1) to move disks B->C by renaming the pins. There we go, we have a stack based solution running in exponential time.
  It's one of the easiest problem in algorithm design, but running the solution by hand would give you a PTSD.

Is this a hard problem to solve? I've not attempted it yet myself.

I seem to remember this was a problem in Advent of Code one year?

I'm imagining there are plenty of algorithms to solve this already, right? With varying numbers of towers and plates? A general solution for solvable amounts of each? Maybe?

This is not a hard problem once you wrap your head around it. It is the earliest that some programmers learn about recursion which has a lot of pitfalls and can be frustrating at times.
- Ah okay, that's where the trauma comes from then, perhaps? 😅 Just being new to a concept and perhaps starting out with a problem that is a little too big while at the same time learning the concept?
- Thank god my first time was building a dynamic tree with loads of metadata and sorting from database records and not some strange game 😐
It's an easy problem to solve... eventually - it's more annoying to solve optimally and that's what programmers usually get handed as a play problem within a year or two of starting to tinker.

Hanoi flashbacks

In myuniversity, we used to play with these to find the fastest path in AI (A*, first depth etc)

Y'all need to play some Dr. Nim. That's a REAL programmer's board game https://boardgamegeek.com/boardgame/23630/the-amazing-dr-nim

Amazing, an analogue computer from 60-s dedicated solely to one task. This is what steampunk ASIC looks like
Vsauce just made a short form about these except a much bigger one

God I can't remember how to do this something about moving tower a to spare pin recursively.

Pretty much. If you can solve it with like 4 then you can solve it with any amount.
- Yeah I remember it being an exponential amount of movements tho.

"You mean I just made a very complicated array-manipulating way of calculating (2^n)-1?"

Lettme introduce you to ackermann's function:

    
int ack(int m, int n) {
    if (m == 0) {
        return n+1;
    } else if((m > 0) && (n == 0)){
        return ack(m-1, 1);
    } else if((m > 0) && (n > 0)) {
        return ack(m-1, ack(m, n-1));
    }
}

You won't run out of stackoverflows any time soon.

Towers of Hanoi? I don't think so.

Petah?

Idk what is this puzzle called? What am i missing here (just learning to program)

Tower of Hanoi