Sorting Algorithms: Difference between revisions

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The numbers we wish to sort are also known as '''keys'''.  
The numbers we wish to sort are also known as '''keys'''.  
<font color=darkgray>


<span id='Comparison_Sort'></span>'''Comparison sort'''.  Cannot do better than n lg n. Proof in a separate article.
<span id='Comparison_Sort'></span>'''Comparison sort'''.  Cannot do better than n lg n. Proof in a separate article.
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* <span id='In-place'></span>'''in-place'''
* <span id='In-place'></span>'''in-place'''
* <span id='Stability'><span>'''stability'''
* <span id='Stability'><span>'''stability'''
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=Sorting Algorithms=
=Sorting Algorithms=

Revision as of 18:00, 5 August 2018

Internal

Overview

Many programs use sorting as an intermediate step, and that is why sorting is considered a fundamental operation in computer science.

The sorting problem if formally defined as follows: given a sequence of n numbers (a1, a2, ... an) provided as input, the algorithm must produce as output a permutation (reordering) (a'1, a'2, ... a'n) of the input sequence such that a'1 ≤ a'2 ≤ ... ≤ a'n. A specific input sequence is called an instance of the sorting problem. Although conceptually we are sorting a sequence, the input comes to the sorting function as an array with n elements.

The numbers we wish to sort are also known as keys.

Comparison sort. Cannot do better than n lg n. Proof in a separate article.

Non-comparison sort.

Sorting algorithms characteristics:

  • in-place
  • stability

Sorting Algorithms