Ruby As A Second Language

#ruby #algorithms #impostersyndrome #programming

This week’s coding challenge in my bootcamp had my brain all knotted up. I was already fatigued from solving (most of) 32 CodeWars katas, but I was scheduled to discuss said challenge — titled “Image Blur 2” — with my mentor Jeremy. I decided to see if I could make any sense of the challenge, which went as follows:

Using Ruby, transform a grid of ones and zeroes such that any zeroes above, beneath and to the sides of a “1” are turned to “1”s (as depicted in the image below the pink "1s" used to be zeroes)

We are currently learning object-oriented programming, so I knew the resulting algorithm would consist of Class and Method definitions. But not even a snippet of a solution would come to me — not that evening, anyhow. So I decided to describe my would-be code in plain English:

Locate the cells with a value of “1”.

Check whether there are rows above, beneath or to the sides of said cell.

Check whether the cells adjacent to said cell in these rows have a value of 1.

If yes, leave unchanged; if not, change the value of adjacent cells to 1. Location of cell-in-question: array[row][column] Cell above: array[row-1][column] Cell below: array[row+1][column] Cell on Left: array[row][column-1] Cell on Right: array[row][column+1]

The only code-y part of my write-up is the location of an element within the grid (“array[row][column]”). I emailed my write-up to Jeremy and called it a night. During our session the next day, Jeremy explained that the challenge consisted of 2 main objectives, and that my “vague” conceptualization had all-but-fulfilled the harder objective (whaa???). We spent the rest of the evening translating my write-up to actual code and creating test-cases to ensure my algorithm’s robustness.

This experience has markedly increased my confidence in approaching algorithms; before now, I believed that if I wasn’t “thinking in Ruby” from the get, then my work wasn’t really legit. After all, it is said that native speakers of a language THINK (not just speak) in that language, right? Well, I’m certainly not expert in Ruby (yet!), but I realize that it’s okay — even effective! — to translate from a language that I’m already comfortable with.

Top comments (4)

Ryan Palo • Sep 2 '18

This is super cool! I love Ruby, so thanks for sharing :)

BTW, if you run into any grid/matrix problems in the future that you want to use Ruby for, check out the matrix library that's part of Ruby's standard library.

require 'matrix'

grid = Matrix[[0, 0, 0, 0], [0, 1, 0, 0], [0, 0, 1, 0], [0, 0, 0, 0]]
grid[1, 1]
# => 1
grid[2, 1]
# => 0

Max Cerrina • Sep 2 '18 • Edited

I'm curious, how would you explain this to someone if you were to walk them through step-by-step? I hear so often that a more functional approach can be harder to understand, and I wonder how you personally would approach explaining that code you posted to a beginner so that it was accessible to them, since I know you're very well-versed in functional programming et al and want to share functional programming concepts with others!

I know one thing I've found useful in such contexts when working with students is to use meaningful variable names even though they're longer.