insertion sort

insertion-sort.rb

class Array
  def insertion_sort_imperative
    self.each_index do |j|
      v = self[j]
      i = j - 1
      while (i >= 0) and (self[i] > v) do 
        self[i], self[i + 1] = self[i + 1], self[i]
        i = i - 1
      end
      self[i + 1] = v
    end
    return self    
  end

  def insert(val, array)
    return [val] if array.empty?
    if val > array[0]
      return [array[0]] + insert(val, array[1..-1])
    else
      return [val] + array
    end
  end

  def insertionsort
    arr = []
    self.each do |v|
      arr = insert(v, arr)
    end
    return arr
  end
end