Solve a leetcode problem in BQN and I rant about the joy of programming.

Leetcode

The Leetcode problem is "Set Matrix Zeroes" where we're tasked with setting rows and columns of a matrix that contain zero to be all zeroes.

BQN Solution

   i←⟨
     3‿4⥊⟨0,1,3,0,3,4,5,2,1,3,1,5⟩
     3‿3⥊⟨1,1,1,1,0,1,1,1,1⟩
   ⟩

   Z ← {
     bm←0=𝕩
     a←∨` ∨`⌾⌽ bm
     b←(∨`˘) ((∨`˘)⌾(⌽˘)) bm
     𝕩×a¬∘∨b
   }
   
   ⟨"#1","#2"⟩∾i≍Z¨i
┌─                       
╵ "#1"        "#2"       
  ┌─          ┌─         
  ╵ 0 1 3 0   ╵ 1 1 1    
    3 4 5 2     1 0 1    
    1 3 1 5     1 1 1    
            ┘         ┘  
  ┌─          ┌─         
  ╵ 0 0 0 0   ╵ 1 0 1    
    0 4 5 0     0 0 0    
    0 3 1 0     1 0 1    
            ┘         ┘  
                        ┘

Some other solutions from the BQN Matrix chat room:

   ⊢×0≠∧˝˘∧⌜∧˝           # Marshall & Dzaima (tacit!)
   (≠⥊∧´)˘{𝕩×(𝔽⌾⍉∧𝔽)0≠𝕩} # Dzaima & Rampoina
   {𝕩×(∧˝˘∧≢⥊∧˝)0≠𝕩}     # Dzaima

On the Joy of Programming

It’s been a few months since I’ve written BQN or APL, so I feel like I’m looking at the language family with fresh eyes.

I was struck by the resemblance between solving this leetcode problem and creating art:

  1. I know I’m not the best at either, and many, many people can write more elegant BQN and more elegant poetry than I can (for example)
  2. I can thoroughly enjoy both when detached from any performance metrics - the process is far more valuable to me than the end-product
  3. both can be deeply social actions - sharing your painting with someone and discussing my solution with the BQN chat room are both social and exciting. Even if someone comes back with a more wonderful painting or more terse solution, I enjoy the social interaction just as much.

I stumbled upon this thread on twitter describing how Kurt Vonnegut responded to a letter from a high school English student asking for life advice. In short, his response was to do art and enjoy the process of becoming who you are.

Creating art seems to be central to the importance of life as far as I can tell.

The most recent episode of ArrayCast with Stevan Apter dipped into this as well when the panelists discussed the aesthetic of writing APL. In some ways they were a little reserved about saying they enjoy APL at least in part due to the aesthetic of the language. I don't think this is something to shy away from - if we can't appreciate the beauty of what we do, why are we doing it at all?

I loved working through this rather simple problem.

I loved the process of visualizing the inputs, of thinking through possible solutions while going about my day.

I loved taking my solution to the BQN forum for more gifted and practiced BQN-ers to find far simpler and more elegant solutions than mine.

The whole process felt like writing a poem, and at the end I’m rewarded by sharing this poem with others, seeing what they come up with, and comparing their thoughts with mine.

There is a unique joy and beauty I find in BQN (and APL more broadly), and that’s what keeps me coming back.

As Kurt Vonnegut pointed out, what else could be a more worthwhile way to spend my time?

Please, give it a try, and fall in love with the community while you’re at it.