Omid - Challenge 128

data-challenges
advanced-exercises
🔰 Result AAA AAB AAC AAD ABA ABB ABC
Published

March 24, 2026

Illustration for Omid - Challenge 128

Challenge Description

🔰 Result AAA AAB AAC AAD ABA ABB ABC

Solutions

library(tidyverse)
library(readxl)

path = "files/CH-128 Cartesian Product.xlsx"
test  = read_excel(path, range = "C1:C65")

lets = c("A","B","C","D")

result = expand.grid(lets,lets, lets) %>%
  unite("result", Var1:Var3, sep = "") %>%
  arrange(result)

all.equal(result$result, test$Result)
#> [1] TRUE

  • Logic:

    • Reads the workbook ranges needed for the challenge

  • Strengths:

    • The R solution stays close to the workbook rule and keeps the transformation compact.

  • Areas for Improvement:

    • The code assumes the sheet structure and source ranges remain stable.

  • Gem:

    • The strongest part of the solution is choosing the right intermediate representation before shaping the final output.
import itertools
import pandas as pd

path = "CH-128 Cartesian Product.xlsx"
test = pd.read_excel(path, usecols = "C")
lets = ["A","B","C","D"]
combs = [''.join(p) for p in itertools.product(lets, repeat=3)]

print(all(combs == test["Result"])) # True

  • Logic:

    • Reads the workbook ranges needed for the challenge

    • Applies the rule iteratively until the output stabilizes

  • Strengths:

    • The Python version follows the same rule in a direct dataframe-oriented implementation.

  • Areas for Improvement:

    • The code assumes the workbook layout remains stable, so any sheet redesign would require small adjustments.

  • Gem:

    • The implementation stays close to the original workbook rule instead of adding unnecessary abstraction.

Difficulty Level

This task is moderate:

  • The business rule is readable, but the workbook still requires careful implementation to reach the expected layout.