insertion_sort.rb

# implementation of insertion sort
  # Pick an item from an array
  # compare all items in the sorted sub-list
  # shift all items in the sorted sub-list greater than the item to be sorted
  # insert the item
  # repeat until the list is sorted.

def insertion_sort(arr)
  a_length = arr.length
  a_length.times do |i|
    while i > 0
      if arr[i - 1] > arr[i]
        arr[i], arr[i - 1] = arr[i - 1], arr[i]
      else
        break
      end
      i -= 1
    end
  end
  arr
end

arr = [2, 5, 6, 2, 5425, 54, 5, 4, 12, 7, 3, 5, 5]
print insertion_sort(arr)