Sort using recursion (10.2 Rite of Passage: Sorting) posted by Tyler Bird @ Fri, 11 Jan 2008 22:17:11 -0000

Tyler Bird — Fri, 11 Jan 2008 22:17:11 -0000

I was on the exact same issue and I’m so pleased with myself that I figured it out I thought I’d share.

Keep in mind, that if you want to solve it yourself this gives you the answer and you should disregard the reply…

NOTE: Remember to uncomment the method you’d prefer to run in the sort method.


def sort an_array
  #recursive_sort an_array, [], 0
  #iterative_sort an_array, []
end

def iterative_sort unsorted_array, sorted_array

    i = 0
    loop do

      break if unsorted_array.length == 0

      score     = 0                      
      length    = unsorted_array.length  
      this_word = unsorted_array[i]      

      # count each time this_word is the smallest & count itself once
      unsorted_array.each do |array_word|
        if this_word <= array_word
          score += 1
        end
      end

      # this_word is the smallest when score == length      
      if score == length
        sorted_array.push(this_word)
        unsorted_array.delete(this_word)
        i = 0  # start at the beginning of the array next time.
      else
        i += 1 # increment the array to check the next word.
      end

    end

  sorted_array
end

def recursive_sort unsorted_array, sorted_array, i

  return if unsorted_array.length == 0

    score     = 0                      
    length    = unsorted_array.length  
    this_word = unsorted_array[i]      

    # count each time this_word is the smallest & count itself once
    unsorted_array.each do |array_word|
      if this_word <= array_word
        score += 1
      end
    end

    # this_word is the smallest when score == length      
    if score == length
      sorted_array.push(this_word)
      unsorted_array.delete(this_word)
      i = 0
    else
      i += 1 # increment the array to check the next word.
    end

  recursive_sort unsorted_array, sorted_array, i

  sorted_array
end

messy_array = ['alpha', 'echo', 'delta', 'beta', 'charlie']

puts sort(messy_array)

Sort using recursion (10.2 Rite of Passage: Sorting) posted by Leo Baghdassarian @ Sat, 05 Jan 2008 02:28:20 -0000

Leo Baghdassarian — Sat, 05 Jan 2008 02:28:20 -0000

Only using the methods from the first 10 chapters of the book, the solution hasn’t come to me. What have you come up with?

Recent Posts in 'Sort using recursion (10.2 Rite of Passage: Sorting)' | Pragmatic Forums

Sort using recursion (10.2 Rite of Passage: Sorting) posted by Tyler Bird @ Fri, 11 Jan 2008 22:17:11 -0000

Sort using recursion (10.2 Rite of Passage: Sorting) posted by Leo Baghdassarian @ Sat, 05 Jan 2008 02:28:20 -0000