23 lines
430 B
Ruby
23 lines
430 B
Ruby
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# Shellsort algorithm,
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# see examples in test/shell_sort_test.rb
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module Shell
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def self.sort(array)
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gap = 1
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gap = 3 * gap + 1 while gap < array.size / 3
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while gap > 0
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gap.upto(array.size - 1) do |i|
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j = i
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while j > 0 && array[j] < array[j - gap]
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array[j], array[j - gap] = array[j - gap], array[j]
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j -= gap
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end
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end
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gap /= 3
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end
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array
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end
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end
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