32 lines
1.0 KiB
Plaintext
32 lines
1.0 KiB
Plaintext
== Shell Sort ==
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Stats::
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:: Worst Case Performance: O(n^2^)
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:: Best Case Performance: O(n log n)
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:: Created in 1959 by Donald *Shell*
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=== Psuedocode ===
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{{{
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// This is the array to be sorted
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gaps = [701, 301, 132, 57, 23, 10, 4, 1]
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// Start with the largest gap and work down to a gap of 1
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foreach(gap in gaps) {
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// Do a gapped insertion sort for this gap size.
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// The first gap elements a[0..gap-1] are already in gapped order
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// keep adding one more element until the entire array is gap sorted
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for(i = gap; i < n; i += 1) {
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// Add gaps[i] to the elements that have been gap sorted
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// save gaps[i] in temp and make a hole at position i
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temp = gaps[i]
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// Shift earlier gap-sorted elements up until the correct location for gaps[i] is found
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for(j = i; j >= gap and gaps[j - gap] > temp; j -= gap) {
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gaps[j] = gaps[j - gap]
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}
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// Put temp (the original gaps[i]) in its correct location
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gaps[j] = temp
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}
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}
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}}}
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=== Additional Info ===
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Wikipedia Article: [http://en.wikipedia.org/wiki/Shell_sort]
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