Sorting techniques
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This document discusses sorting algorithms. It explains that sorting refers to arranging data in a specified order like numerical or alphabetical. Selection sort is described as finding the minimum element and swapping it into the correct position in each pass through the array until sorted. An example of selection sort is provided, showing the steps and swaps to sort an array of numbers.
![ Let A be a list of n numbers. Sorting A refers to the
operation of rearranging the elements of A So they
are in increasing order ,So that,
A[1]<A[2]<A[3]<……….<A[N]
Example :-
List is- 8,4,19,2,7,13,5,16
After Sorting :-
List is-2,4,5,7,8,13,16,19](https://image.slidesharecdn.com/sortingtechniques-170708003255/85/Sorting-techniques-10-320.jpg)
Sorting techniques
- 1. 1
- 2. Introduction Sorting Selection Sort Bubble Sort Bubble Sorting:- Example
- 3. Sorting and searching are fundamental operations in computer science. Sorting refers to operation of arranging data in some given order , such as increasing or decreasing ,with numerical data or with character data. Generally, collections of data are presented in a sorted manner.
- 4. Let A be a list of n elements A1,A2,……An in Memory. Sorting A refers to the operation of rearranging the contents of A so that they are in increasing in order, so that A1<A2<A3<…..<An
- 5. Sorting = ordering. Sorted = ordered based on a particular way. Examples of Sorting: Words in a dictionary are sorted (and case distinctions are ignored). Files in a directory are often listed in sorted order. The index of a book is sorted (and case distinctions are ignored).
- 6. A relatively easy to understand algorithm Sorts an array in passes Each pass selects the next smallest element At the end of the pass, places it where it belongs Efficiency is O(n2 ), hence called a quadratic sort Performs: O(n2 ) comparisons O(n) exchanges (swaps)
- 7. 7 Idea: Find the smallest element in the array Exchange it with the element in the first position Find the second smallest element and exchange it with the element in the second position Continue until the array is sorted Disadvantage: Running time depends only slightly on the amount of order in the file
- 8. 35 65 30 60 20 scan 0-4, smallest 20 swap 35 and 20 20 65 30 60 35 scan 1-4, smallest 30 swap 65 and 30 20 30 65 60 35 scan 2-4, smallest 35 swap 65 and 35 20 30 35 60 65 scan 3-4, smallest 60 swap 60 and 60 20 30 35 60 65 done
- 9. 1. for fill = 0 to n-2 do // steps 2-6 form a pass 2. set posMin to fill 3. for next = fill+1 to n-1 do 4. if item at next < item at posMin 5. set posMin to next 6. Exchange item at posMin with one at fill
- 10. Let A be a list of n numbers. Sorting A refers to the operation of rearranging the elements of A So they are in increasing order ,So that, A[1]<A[2]<A[3]<……….<A[N] Example :- List is- 8,4,19,2,7,13,5,16 After Sorting :- List is-2,4,5,7,8,13,16,19
- 11. Suppose the following numbers are stored in an array A:- 53,21,65,27,70,8,99,1. Pass1-21,53,65,27,70,8,99,1 21,53,65,27,70,8,99,1 21,53,27,65,70,8,99,1 21,53,27,65,70,8,99,1 21,53,27,65,8,70,99,1 21,53,27,65,8,70,99,1 21,53,27,65,8,70,1,99
- 13. Pass4- 21,27,8,53,1,65,70,99 21,8,27,53,1,65,70,99 21,8,27,1,53,65,70,99 Pass5- 21,8,27,1,53,65,70,99 8,21,27,1,53,65,70,99 8,21,1,27,53,65,70,99 Pass6- 8,21,1,27,53,65,70,99 8,1,21,27,53,65,70,99 Pass7- 1,8,21,27,53,65,70,99 SORTED LIST IS:- 1,8,21,27,53,65,70,99