Sorting algorithm
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The document discusses four sorting algorithms: selection sort, bubble sort, insertion sort, and merge sort. It provides pseudocode for the selection sort algorithm and describes how it works by making successive passes through an array and swapping elements until the array is fully sorted. Bubble sort and insertion sort are also described as making multiple passes through an array, comparing and swapping adjacent elements until the array is in order. Pseudocode is provided for the bubble sort and insertion sort algorithms.
![Selection Sort Algorithm
Step 1. [Starting Selection Loop]
Repeat step 2 For S=1 to N-1 by 1
Step 2. [Starting Selection Loop]
Repeat step 3 For C=S+1 to N by 1
Step 3. [Compare Element]
If(A[s]> A[c]) Then
Temp=A[S]
A[S]=A[C]
A[S]=Temp
Exit](https://image.slidesharecdn.com/sortingalgorithm-190102050847/85/Sorting-algorithm-26-320.jpg)
![Bubble Sort
Write an algorithm to sort an array A consisting of
N elements in ascending order using bubble sort
Suppose variable U represents the control variable
for upper loop to control the number of iteration .
Similarly , variable I represent the control variable
for inner loop that scans the array starting from
element A[1] to A[U]](https://image.slidesharecdn.com/sortingalgorithm-190102050847/85/Sorting-algorithm-52-320.jpg)
![Cont.……
1. Set U=N
2. [Upper loop]
Repeat step 3 to 7 while (U>=1)
3. Set I=1
4. [Inner Loop]
Repeat step 5 to 6 while (I<=U)
5. IF A[I]>A[I+1]
T=A[I]
A[I]=A[I+1]
A[I+1]=T END IF
6. I=I+1
7. U=U-1
8. EXIT](https://image.slidesharecdn.com/sortingalgorithm-190102050847/85/Sorting-algorithm-53-320.jpg)
![Algorithm for insertion sort
Write an algorithm to sort an array A
consisting of N elements in ascending order
using Insertion sort method
Suppose variable U represents the control
variable for upper loop to control the number
of iteration . Similarly , variable I represent
the control variable for inner loop that scans
the array starting from element A[1] to A[U]](https://image.slidesharecdn.com/sortingalgorithm-190102050847/85/Sorting-algorithm-56-320.jpg)
![CONT.….
1. REPEAT STEP 2 TO 6 FOR C=1 TO N
2. TEMP=A[C]
3. L=C
4. REPEAT STEP 3 to 7 WHILE (L>0 AND TEMP<A[L-1])
5. A[L]=A[L-1] [END OF STEP 4 INNER LOOP]
6. A[L]=TEMP [INSERT VALUE]
[END OF STEP 1 UPPER LOOP]
7. EXIT](https://image.slidesharecdn.com/sortingalgorithm-190102050847/85/Sorting-algorithm-57-320.jpg)
Sorting algorithm
- 2. Sorting Four algorithms are described 1. Selection sort 2. Bubble sort 3. Insertion Sort 4. Merge Sort (Assignment)
- 3. Selection Sort In the first pass, each item in the list is compared with the first item in the list If the first item in the list is bigger then the item being compared then they are swapped.
- 4. Selection Sort 7 5 9 6 1 8 2 0 3 4 1st Comparison Swap
- 5. Selection Sort 5 7 9 6 1 8 2 0 3 4
- 6. Selection Sort 5 7 9 6 1 8 2 0 3 4 2nd Comparison
- 7. Selection Sort 5 7 9 6 1 8 2 0 3 4 3rd Comparison
- 8. Selection Sort 5 7 9 6 1 8 2 0 3 4 4th Comparison Swap
- 9. Selection Sort 1 7 9 6 5 8 2 0 3 4 5th Comparison
- 10. Selection Sort 1 7 9 6 5 8 2 0 3 4 6th Comparison
- 11. Selection Sort 1 7 9 6 5 8 2 0 3 4 7th Comparison Swap
- 12. Selection Sort 0 7 9 6 5 8 2 1 3 4
- 13. Selection Sort 0 7 9 6 5 8 2 1 3 4 8th Comparison
- 14. Selection Sort 0 7 9 6 5 8 2 1 3 4 9th Comparison
- 15. Selection Sort 0 7 9 6 5 8 2 1 3 4 1st Comparison
- 16. Selection Sort 0 7 9 6 5 8 2 1 3 4 2nd Comparison Swap
- 17. Selection Sort 0 6 9 7 5 8 2 1 3 4
- 18. Selection Sort 0 6 9 7 5 8 2 1 3 4 3rd Comparison Swap
- 19. Selection Sort 0 5 9 7 6 8 2 1 3 4
- 20. Selection Sort 0 5 9 7 6 8 2 1 3 4 4th Comparison
- 21. Selection Sort 0 5 9 7 6 8 2 1 3 4 5th Comparison Swap
- 22. Selection Sort 0 2 9 7 6 8 5 1 3 4
- 23. Selection Sort 0 2 9 7 6 8 5 1 3 4 And so on…
- 24. Selection Sort until… 0 1 2 3 4 5 6 7 8 9
- 25. Selection Sort Must make N-1 passes through list even when fully sorted or partially sorted
- 26. Selection Sort Algorithm Step 1. [Starting Selection Loop] Repeat step 2 For S=1 to N-1 by 1 Step 2. [Starting Selection Loop] Repeat step 3 For C=S+1 to N by 1 Step 3. [Compare Element] If(A[s]> A[c]) Then Temp=A[S] A[S]=A[C] A[S]=Temp Exit
- 27. Bubble Sort Bubble sort is a simple algorithm that repeatedly steps through the list, compares adjacent pairs and swap them if they are in wrong order. The pass through the list is repeated until list is sorted.
- 28. Bubble sort Example 7 5 9 6 1 8 2 0 3 4 First Comparison Swap
- 29. Bubble sort 5 7 9 6 1 8 2 0 3 4
- 30. Bubble sort 5 7 9 6 1 8 2 0 3 4 Second Comparison
- 31. Bubble sort 5 7 9 6 1 8 2 0 3 4 Third Comparison Swap
- 32. Bubble sort 5 7 6 9 1 8 2 0 3 4
- 33. Bubble sort 5 7 6 9 1 8 2 0 3 4 Fourth Comparison Swap
- 34. Bubble sort 5 7 6 1 9 8 2 0 3 4
- 35. Bubble sort 5 7 6 1 9 8 2 0 3 4 Fifth Comparison Swap
- 36. Bubble sort 5 7 6 1 8 9 2 0 3 4
- 37. Bubble sort 5 7 6 1 8 9 2 0 3 4 Sixth Comparison Swap
- 38. Bubble sort 5 7 6 1 8 2 9 0 3 4
- 39. Bubble sort 5 7 6 1 8 2 9 0 3 4 Seventh Comparison Swap
- 40. Bubble sort 5 7 6 1 8 2 0 9 3 4
- 41. Bubble sort 5 7 6 1 8 2 0 9 3 4 8th Comparison Swap
- 42. Bubble sort 5 7 6 1 8 2 0 3 9 4
- 43. Bubble sort 5 7 6 1 8 2 0 3 9 4 9th Comparison Swap
- 44. Bubble sort 5 7 6 1 8 2 0 3 4 9 Notice… we are sorting list into an ascending list. The largest number is now at the end of the list…where it should be! This completes the first pass through the list.
- 45. Bubble sort 5 7 6 1 8 2 0 3 4 9 The process begins again. 1st Comparison Second Pass
- 46. Bubble sort 5 7 6 1 8 2 0 3 4 9 2nd Comparison Swap Second Pass
- 47. Bubble sort 5 6 7 1 8 2 0 3 4 9 Second Pass
- 48. Bubble sort 5 6 7 1 8 2 0 3 4 9 3rd Comparison Swap Second Pass
- 49. Bubble sort 5 6 1 7 8 2 0 3 4 9 Second Pass
- 50. Bubble sort 5 6 1 7 8 2 0 3 4 9 4th Comparison Second Pass
- 51. Bubble sort 5 6 1 7 8 2 0 3 4 9 5th Comparison Swap Second Pass
- 52. Bubble Sort Write an algorithm to sort an array A consisting of N elements in ascending order using bubble sort Suppose variable U represents the control variable for upper loop to control the number of iteration . Similarly , variable I represent the control variable for inner loop that scans the array starting from element A[1] to A[U]
- 53. Cont.…… 1. Set U=N 2. [Upper loop] Repeat step 3 to 7 while (U>=1) 3. Set I=1 4. [Inner Loop] Repeat step 5 to 6 while (I<=U) 5. IF A[I]>A[I+1] T=A[I] A[I]=A[I+1] A[I+1]=T END IF 6. I=I+1 7. U=U-1 8. EXIT
- 54. Insertion Sort In insertion sort algorithm, compare the value until all the previous value is lesser than compared value. Insertion sort is more efficient than bubble sort because in insertion sort the elements comparisons are lesser as compared to bubble sort. Insertion sort is suitable for small data.
- 56. Algorithm for insertion sort Write an algorithm to sort an array A consisting of N elements in ascending order using Insertion sort method Suppose variable U represents the control variable for upper loop to control the number of iteration . Similarly , variable I represent the control variable for inner loop that scans the array starting from element A[1] to A[U]
- 57. CONT.…. 1. REPEAT STEP 2 TO 6 FOR C=1 TO N 2. TEMP=A[C] 3. L=C 4. REPEAT STEP 3 to 7 WHILE (L>0 AND TEMP<A[L-1]) 5. A[L]=A[L-1] [END OF STEP 4 INNER LOOP] 6. A[L]=TEMP [INSERT VALUE] [END OF STEP 1 UPPER LOOP] 7. EXIT