Omid - Challenge 68

data-challenges
advanced-exercises
🔰 Create a formula to receive a number n as input and generate a Triangular with a height equal to n using ’*’ characters.
Published

March 24, 2026

Illustration for Omid - Challenge 68

Challenge Description

🔰 Create a formula to receive a number n as input and generate a Triangular with a height equal to n using “*” characters.

Solutions

library(tidyverse)

draw_triangle = function(n) {
  if (n %% 2 == 0) {
    return("Not Possible")
  } else {
    x = ceiling(n / 2)
    seq = seq(1, x)
    
    mat = matrix("", n, x)
    for (i in 1:x) {
      mat[i, 1:seq[i]] = "*"
    }
    for (i in 1:(x - 1)) {
      mat[n - i + 1, ] = mat[i, ]
    }
    
    print(mat)
  }
}


draw_triangle(7)

  • Logic:

    • Applies the rule iteratively until the output stabilizes

  • 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 numpy as np

def draw_triangle(n):
    if n % 2 == 0:
        print("Not Possible")
    else:
        x = (n + 1) // 2
        seq = list(range(1, x + 1))       
        mat = np.full((n, x), "", dtype=object)
        for i in range(x):
            mat[i, :seq[i]] = "*"
        for i in range(1, x):
            mat[n - i, :] = mat[i - 1, :]
        print(mat)

draw_triangle(7)

  • Logic:

    • 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.