insertion_sort.rb

def insert(array, right_index, value)
  i = right_index
  puts right_index
  while array[i] > value
    break if i < 0
    array[i + 1] = array[i]
    i -= 1
  end
  array[i + 1] = value
end

def insertion_sort(array)
  (0...array.count - 1).each do |n|
    insert(array, n, array[n+1])
  end
  array
end

array = [5, 7, 19, 2, -4]
insertion_sort(array)
# => [-4, 2, 5, 7, 19]