unit-iii sorting lesson plan-1 insertion sort, selection sort
TRANSCRIPT
UNIT-IIISORTING
Lesson Plan-1
Insertion Sort, Selection Sort
Contents
Evocation Objective Introduction-Sorting Sort Classifications Sort Insertion Sort Selection Sort Mind map Summary
ANNEXURE-IEvocation
Objective
To study the basic concept of sorting techniques
To discuss about the insertion sort and selection sort algorithm with examples
ANNEXURE-IIIntroduction-Sorting
A sorting algorithm is an algorithm that puts elements of a list in a certain order
Consider listx1, x2, x3, … xn
We seek to arrange the elements of the list in order• Ascending or descending• For example, to arrange the elements in ascending orderStart 1 23 2 56 9 8 10 100End 1 2 8 9 10 23 56 100
Some O(n2) schemes• Easy to understand and implement• Inefficient for large data sets
Sort Classifications
Sort
Internal External
Insertion Selection Exchange
Insertion Selection
Shell Heap
Bubble
Quick
Natural Balanced
Polyphase
Sort
Internal Sort
• Data are held in primary memory during sorting process
External Sort
• Use primary memory for data currently being sorted
Sort Order
• Data sorted in ascending or descending sequence
• Identifies sequence of sorted data, ascending or descending
Example
• Ascending sequence - Dictionary, telephone book
• Descending sequence - Percentage of games won in sporting event such as base ball
Sort
Sort Stability
• Attribute of sort indicating data with equal keys maintain relative input order in output
Unsorted data Stable sort Unstable sort
365 blue212 green876 white212 yellow119 purple737 green212 blue443 red567 yellow
119 purple212 green212 yellow212 blue365 blue443 red567 yellow737 green876 white
119 purple212 blue212 green212 yellow365 blue443 red567 yellow737 green876 white
Sort
Sort Efficiency
• Measure of relative efficiency of sort
• Estimate of number of comparisons and moves required
to order unordered list
Passes
• During sorting, data traversed many times
• Each traversal of data is referred to as sort pass
• Sort pass traverse whole list or section of list
Evocation
Insertion Sort
In each pass of insertion sort, one or more pieces of data are inserted into correct location in ordered list
Most common sort technique used by card players
Pick up each card, then insert into proper sequence in hand
Repeatedly insert a new element into an already sorted list
List is divided into two parts: Sorted and Unsorted In each pass the first element of unsorted sublist is transferred
to sorted sublist by inserting at appropriate place If list contains n elements, it will take n-1 passes to sort data
Insertion Sort Example
Contd.,
ANNEXURE-IIIProgressive Muscular Relaxation
Forehead
• Wrinkle your forehead and arch your eyebrows
• Hold; then relax
Eyes
• Close your eyes tightly.
• Hold; then relax
Nose
• Wrinkle your nose and flare your nostrils.
• Hold; then relax
Tongue
• Push your tongue firmly against the roof of your mouth
• Hold; then relax
Optical Illusion
What do you see in the image below?
Logo Identification
Abbreviation
• AIAA
• BAE
• BNSC
• A&A
Evocation
Selection Sort
List is divided into two sublists, sorted and unsorted which are divided by imaginary wall
In each pass, the smallest element is selected from unsorted sublist and exchanged with element at beginning of unsorted sublist
Make passes through a listOn each pass reposition correctly some element
Selection Sort Example
ANNEXURE-IVMind Map
Sorting
Classification
Insertion Sort Selection SortAlgorithm
ExampleProgram
Algorithm
Example Program
ANNEXURE-VSummary
• Sorting is one of the most common data processing applications
• Sorting algorithms are classified as either internal or external
• Data may be sorted in ascending or descending order
• Sort stability is an attribute of sort indicating data with equal keys maintain relative input order in output
• Sort efficiency is a measure of relative efficiency of sort
• Each traversal of data during sorting process is referred to as pass
Summary
• In Straight insertion sort, list is divided into two sublists: Sorted and Unsorted
• In each pass the first element of unsorted sublist is transferred to sorted sublist by inserting at appropriate place
• In Straight selection sort the list is divided into two sublists, sorted and unsorted
• In each pass, the process selects the smallest element from unsorted sublist and exchanged with element at beginning of unsorted sublist