Overview of Sorting

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Overview of Sorting

• by Ron Peterson

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Variety of Algorithms

• There are a lot of different approaches to
  sorting, not just different programs that use
  similar methods.
• Donald Knuths, The Art of Computer Programming,
  Vol. 3, documents dozens of algorithmic methods
  for sorting.
• Examples bubble, insertion, selection, Shell,
  merge, heap, quick, radix are all prefixes of
  names of sorts.

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More Sort Names

• Bubble sort Cocktail sort Odd-even sort
  Comb sort Gnome sort Quicksort Selection
  sort Heapsort Smoothsort Cartesian tree
  sort Tournament sort Cycle sort Insertion
  sort Shell sort Tree sort Library sort
  Patience sorting Monkey-puzzle sort Merge
  sort Polyphase merge sort Strand sort
  American flag sort Bead sort Bucket sort
  Burstsort Counting sort Pigeonhole sort
  Proxmap sort Radix sort Flashsort Bitonic
  sorter Batcher odd-even mergesort Timsort
  Introsort Spreadsort UnShuffle sort JSort
  Spaghetti sort Pancake sort

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Categories by Efficiency

• Simple sorts O(N2)
• Bubble, selection, insertion sorts
• Intermediate sorts
• Shell O(Nlog2 N)
• Efficient sorts O(Nlog N)
• Quicksort, merge sort, Heap sort
• Specialty sorts
• Radix O(C) ( of digits per value)

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What you should know

• For each sort discussed
• The name
• Its efficiency
• Average, best, and worst
• How it works
• Study the individual sorts in the book and look
  at the videos on the syllabus link

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2 more topics

• Stable sorts
• Used for multi-key sorts like First/Last name
• Does not change order within key group
• Merge sort is typically a stable sort
• STL sort algorithms
• Same interface for each (begin-it, end-it, opl)
• Main approaches
• sort(..) stable_sort(..) make_heap(..),
  sort_heap(..) plus a few tools to build others