Method: Algorithms::Sort.shell_sort

Defined in:
lib/algorithms/sort.rb

.shell_sort(container) ⇒ Object

Shell sort: Similar approach as insertion sort but slightly better. Requirements: Needs to be able to compare elements with <=>, and the [] []= methods should be implemented for the container. Time Complexity: О(n^2) Space Complexity: О(n) total, O(1) auxiliary Stable: Yes

Algorithms::Sort.shell_sort [5, 4, 3, 1, 2] => [1, 2, 3, 4, 5]



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# File 'lib/algorithms/sort.rb', line 122

def self.shell_sort(container)
  increment = container.size/2
  while increment > 0 do
    (increment..container.size-1).each do |i|
      temp = container[i]
      j = i
      while j >= increment && container[j - increment] > temp do
        container[j] = container[j-increment]
        j -= increment
      end
      container[j] = temp
    end
    increment = (increment == 2 ? 1 : (increment / 2.2).round)
  end
  container
end