it is basically belongs to dsa of python ppt which includes the methology and its algorithms for sorting of data in python........

1. Sorting

2. Introduction
• Common problem: sort a list of values, starting
from lowest to highest.
– List of exam scores
– Words of dictionary in alphabetical order
– Students names listed alphabetically
– Student records sorted by ID#
• Generally, we are given a list of records that have
keys. These keys are used to define an ordering of
the items in the list.

3. Quadratic Sorting Algorithms
• We are given n records to sort.
• There are a number of simple sorting
algorithms whose worst and average case
performance is quadratic O(n2):
– Selection sort
– Insertion sort
– Bubble sort

4. Sorting an Array of Integers
• Example: we
are given an
array of six
integers that
we want to
sort from
smallest to
largest
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[1] [2] [3] [4] [5] [6]
[0] [1] [2] [3] [4] [5]

5. 0
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[1] [2] [3] [4] [5] [6]
The Selection Sort Algorithm
• Start by
finding the
smallest
entry.
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70
[1] [2] [3] [4] [5] [6]
[0] [1] [2] [3] [4] [5]

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[1] [2] [3] [4] [5] [6]
The Selection Sort Algorithm
• Swap the
smallest
entry with
the first
entry.
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70
[1] [2] [3] [4] [5] [6]
[0] [1] [2] [3] [4] [5]

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[1] [2] [3] [4] [5] [6]
The Selection Sort Algorithm
• Swap the
smallest
entry with
the first
entry.
0
10
20
30
40
50
60
70
[1] [2] [3] [4] [5] [6]
[0] [1] [2] [3] [4] [5]

8. 0
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[1] [2] [3] [4] [5] [6]
The Selection Sort Algorithm
• Part of the
array is now
sorted.
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70
[1] [2] [3] [4] [5] [6]
Sorted side Unsorted side
[0] [1] [2] [3] [4] [5]

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[1] [2] [3] [4] [5] [6]
0
10
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50
60
70
[1] [2] [3] [4] [5] [6]
The Selection Sort Algorithm
• Find the
smallest
element in
the unsorted
side.
Sorted side Unsorted side
[0] [1] [2] [3] [4] [5]

10. 0
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[1] [2] [3] [4] [5] [6]
0
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70
[1] [2] [3] [4] [5] [6]
The Selection Sort Algorithm
• Swap with
the front of
the unsorted
side.
Sorted side Unsorted side
[0] [1] [2] [3] [4] [5]

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[1] [2] [3] [4] [5] [6]
0
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50
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70
[1] [2] [3] [4] [5] [6]
The Selection Sort Algorithm
• We have
increased the
size of the
sorted side
by one
element.
Sorted side Unsorted side
[0] [1] [2] [3] [4] [5]

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[1] [2] [3] [4] [5] [6]
0
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70
[1] [2] [3] [4] [5] [6]
The Selection Sort Algorithm
• The process
continues...
Sorted side Unsorted side
Smallest
from
unsorted
[0] [1] [2] [3] [4] [5]

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[1] [2] [3] [4] [5] [6]
0
10
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70
[1] [2] [3] [4] [5] [6]
The Selection Sort Algorithm
• The process
continues...
Sorted side Unsorted side
[0] [1] [2] [3] [4] [5]

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[1] [2] [3] [4] [5] [6]
0
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70
[1] [2] [3] [4] [5] [6]
The Selection Sort Algorithm
• The process
continues...
Sorted side Unsorted side
Sorted side
is bigger
[0] [1] [2] [3] [4] [5]

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[1] [2] [3] [4] [5] [6]
0
10
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30
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50
60
70
[1] [2] [3] [4] [5] [6]
The Selection Sort Algorithm
• The process
keeps adding
one more
number to the
sorted side.
• The sorted side
has the smallest
numbers,
arranged from
small to large.
Sorted side Unsorted side
[0] [1] [2] [3] [4] [5]

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70
[1] [2] [3] [4] [5] [6]
0
10
20
30
40
50
60
70
[1] [2] [3] [4] [5] [6]
The Selection Sort Algorithm
• We can stop
when the
unsorted side
has just one
number, since
that number
must be the
largest number.
[0] [1] [2] [3] [4] [5]
Sorted side Unsorted sid

17. 0
10
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70
[1] [2] [3] [4] [5] [6]
The Selection Sort Algorithm
• The array is
now sorted.
• We repeatedly
selected the
smallest
element, and
moved this
element to the
front of the
unsorted side. [0] [1] [2] [3] [4] [5]

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[1] [2] [3] [4] [5] [6]
The Insertion Sort Algorithm
• The Insertion
Sort algorithm
also views the
array as having
a sorted side
and an
unsorted side.
[0] [1] [2] [3] [4] [5]

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[1] [2] [3] [4] [5] [6]
The Insertion Sort Algorithm
• The sorted
side starts
with just the
first
element,
which is not
necessarily
the smallest
element.
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10
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30
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70
[1] [2] [3] [4] [5] [6]
[0] [1] [2] [3] [4] [5]
Sorted side Unsorted side

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[1] [2] [3] [4] [5] [6]
The Insertion Sort Algorithm
• The sorted
side grows
by taking the
front
element
from the
unsorted
side... 0
10
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30
40
50
60
70
[1] [2] [3] [4] [5] [6]
[0] [1] [2] [3] [4] [5]
Sorted side Unsorted side

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[1] [2] [3] [4] [5] [6]
The Insertion Sort Algorithm
• ...and
inserting it
in the place
that keeps
the sorted
side
arranged
from small
to large.
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10
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70
[1] [2] [3] [4] [5] [6]
[0] [1] [2] [3] [4] [5]
Sorted side Unsorted side

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[1] [2] [3] [4] [5] [6]
The Insertion Sort Algorithm
0
10
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70
[1] [2] [3] [4] [5] [6]
[0] [1] [2] [3] [4] [5]
Sorted side Unsorted side

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[1] [2] [3] [4] [5] [6]
The Insertion Sort Algorithm
• Sometimes
we are lucky
and the new
inserted item
doesn't need
to move at
all.
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70
[1] [2] [3] [4] [5] [6]
[0] [1] [2] [3] [4] [5]
Sorted side Unsorted side

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[1] [2] [3] [4] [5] [6]
The Insertionsort Algorithm
• Sometimes
we are lucky
twice in a
row.
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70
[1] [2] [3] [4] [5] [6]
[0] [1] [2] [3] [4] [5]
Sorted side Unsorted side

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[1] [2] [3] [4] [5] [6]
How to Insert One Element
Copy the
new element
to a separate
location.
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70
[1] [2] [3] [4] [5] [6]
[3] [4] [5] [6] [0] [1] [2] [3] [4] [5]
Sorted side Unsorted side

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[1] [2] [3] [4] [5] [6]
How to Insert One Element
Shift
elements in
the sorted
side,
creating an
open space
for the new
element.
0
10
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30
40
50
60
70
[1] [2] [3] [4] [5] [6]
[3] [4] [5] [6] [0] [1] [2] [3] [4] [5]

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[1] [2] [3] [4] [5] [6]
0
10
20
30
40
50
60
70
[1] [2] [3] [4] [5] [6]
How to Insert One Element
Shift
elements in
the sorted
side,
creating an
open space
for the new
element.
[3] [4] [5] [6]
0
10
20
30
40
50
60
70
[1] [2] [3] [4] [5] [6]
[0] [1] [2] [3] [4] [5]

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[1] [2] [3] [4] [5] [6]
0
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70
[1] [2] [3] [4] [5] [6]
How to Insert One Element
Continue
shifting
elements...
[3] [4] [5] [6]
0
10
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40
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60
70
[1] [2] [3] [4] [5] [6]
[0] [1] [2] [3] [4] [5]

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[1] [2] [3] [4] [5] [6]
0
10
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50
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70
[1] [2] [3] [4] [5] [6]
How to Insert One Element
Continue
shifting
elements...
[3] [4] [5] [6]
0
10
20
30
40
50
60
70
[1] [2] [3] [4] [5] [6]
[0] [1] [2] [3] [4] [5]

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[1] [2] [3] [4] [5] [6]
0
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[1] [2] [3] [4] [5] [6]
How to Insert One Element
...until you
reach the
location for
the new
element.
[3] [4] [5] [6]
0
10
20
30
40
50
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70
[1] [2] [3] [4] [5] [6]
[0] [1] [2] [3] [4] [5]

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[1] [2] [3] [4] [5] [6]
0
10
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70
[1] [2] [3] [4] [5] [6]
How to Insert One Element
Copy the
new element
back into the
array, at the
correct
location.
[3] [4] [5] [6] [0] [1] [2] [3] [4] [5]
Sorted side Unsorted sid

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[1] [2] [3] [4] [5] [6]
How to Insert One Element
[2] [3] [4] [5] [6]
• The last
element
must also be
inserted.
Start by
copying it...
[0] [1] [2] [3] [4] [5]
Sorted side Unsorted sid

33. 0
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[1] [2] [3] [4] [5] [6]
Sorted Result
[0] [1] [2] [3] [4] [5]

34. 0
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70
[1] [2] [3] [4] [5] [6]
The Bubble Sort Algorithm
• The Bubble
Sort algorithm
looks at pairs
of entries in
the array, and
swaps their
order if
needed.
[0] [1] [2] [3] [4] [5]

35. 0
10
20
30
40
50
60
70
[1] [2] [3] [4] [5] [6]
The Bubble Sort Algorithm
• The Bubble
Sort algorithm
looks at pairs
of entries in
the array, and
swaps their
order if
needed.
[0] [1] [2] [3] [4] [5]
Swap?

36. 0
10
20
30
40
50
60
70
[1] [2] [3] [4] [5] [6]
The Bubble Sort Algorithm
• The Bubble
Sort algorithm
looks at pairs
of entries in
the array, and
swaps their
order if
needed.
[0] [1] [2] [3] [4] [5]
Yes!

37. 0
10
20
30
40
50
60
70
[1] [2] [3] [4] [5] [6]
The Bubble Sort Algorithm
• The Bubble
Sort algorithm
looks at pairs
of entries in
the array, and
swaps their
order if
needed.
[0] [1] [2] [3] [4] [5]
Swap?

38. 0
10
20
30
40
50
60
70
[1] [2] [3] [4] [5] [6]
The Bubble Sort Algorithm
• The Bubble
Sort algorithm
looks at pairs
of entries in
the array, and
swaps their
order if
needed.
[0] [1] [2] [3] [4] [5]
No.

39. 0
10
20
30
40
50
60
70
[1] [2] [3] [4] [5] [6]
The Bubble Sort Algorithm
• The Bubble
Sort algorithm
looks at pairs
of entries in
the array, and
swaps their
order if
needed.
[0] [1] [2] [3] [4] [5]
Swap?

40. 0
10
20
30
40
50
60
70
[1] [2] [3] [4] [5] [6]
The Bubble Sort Algorithm
• The Bubble
Sort algorithm
looks at pairs
of entries in
the array, and
swaps their
order if
needed.
[0] [1] [2] [3] [4] [5]
No.

41. 0
10
20
30
40
50
60
70
[1] [2] [3] [4] [5] [6]
The Bubble Sort Algorithm
• The Bubble
Sort algorithm
looks at pairs
of entries in
the array, and
swaps their
order if
needed.
[0] [1] [2] [3] [4] [5]
Swap?

42. 0
10
20
30
40
50
60
70
[1] [2] [3] [4] [5] [6]
The Bubble Sort Algorithm
• The Bubble
Sort algorithm
looks at pairs
of entries in
the array, and
swaps their
order if
needed.
[0] [1] [2] [3] [4] [5]
Yes!

43. 0
10
20
30
40
50
60
70
[1] [2] [3] [4] [5] [6]
The Bubble Sort Algorithm
• The Bubble
Sort algorithm
looks at pairs
of entries in
the array, and
swaps their
order if
needed.
[0] [1] [2] [3] [4] [5]
Swap?

44. 0
10
20
30
40
50
60
70
[1] [2] [3] [4] [5] [6]
The Bubble Sort Algorithm
• The Bubble
Sort algorithm
looks at pairs
of entries in
the array, and
swaps their
order if
needed.
[0] [1] [2] [3] [4] [5]
Yes!

45. 0
10
20
30
40
50
60
70
[1] [2] [3] [4] [5] [6]
The Bubble Sort Algorithm
• Repeat.
[0] [1] [2] [3] [4] [5]
Swap? No.

46. 0
10
20
30
40
50
60
70
[1] [2] [3] [4] [5] [6]
The Bubble Sort Algorithm
• Repeat.
[0] [1] [2] [3] [4] [5]
Swap? No.

47. 0
10
20
30
40
50
60
70
[1] [2] [3] [4] [5] [6]
The Bubble Sort Algorithm
• Repeat.
[0] [1] [2] [3] [4] [5]
Swap? Yes.

48. 0
10
20
30
40
50
60
70
[1] [2] [3] [4] [5] [6]
The Bubble Sort Algorithm
• Repeat.
[0] [1] [2] [3] [4] [5]
Swap? Yes.

49. 0
10
20
30
40
50
60
70
[1] [2] [3] [4] [5] [6]
The Bubble Sort Algorithm
• Repeat.
[0] [1] [2] [3] [4] [5]
Swap? Yes.

50. 0
10
20
30
40
50
60
70
[1] [2] [3] [4] [5] [6]
The Bubble Sort Algorithm
• Repeat.
[0] [1] [2] [3] [4] [5]
Swap? Yes.

51. 0
10
20
30
40
50
60
70
[1] [2] [3] [4] [5] [6]
The Bubble Sort Algorithm
• Repeat.
[0] [1] [2] [3] [4] [5]
Swap? No.

52. 0
10
20
30
40
50
60
70
[1] [2] [3] [4] [5] [6]
The Bubble Sort Algorithm
• Loop over
array n-1
times,
swapping pairs
of entries as
needed.
[0] [1] [2] [3] [4] [5]
Swap? No.

53. 0
10
20
30
40
50
60
70
[1] [2] [3] [4] [5] [6]
The Bubble Sort Algorithm
• Loop over
array n-1
times,
swapping pairs
of entries as
needed.
[0] [1] [2] [3] [4] [5]
Swap? Yes.

54. 0
10
20
30
40
50
60
70
[1] [2] [3] [4] [5] [6]
The Bubble Sort Algorithm
• Loop over
array n-1
times,
swapping pairs
of entries as
needed.
[0] [1] [2] [3] [4] [5]
Swap? Yes.

55. 0
10
20
30
40
50
60
70
[1] [2] [3] [4] [5] [6]
The Bubble Sort Algorithm
• Loop over
array n-1
times,
swapping pairs
of entries as
needed.
[0] [1] [2] [3] [4] [5]
Swap? Yes.

56. 0
10
20
30
40
50
60
70
[1] [2] [3] [4] [5] [6]
The Bubble Sort Algorithm
• Loop over
array n-1
times,
swapping pairs
of entries as
needed.
[0] [1] [2] [3] [4] [5]
Swap? Yes.

57. 0
10
20
30
40
50
60
70
[1] [2] [3] [4] [5] [6]
The Bubble Sort Algorithm
• Loop over
array n-1
times,
swapping pairs
of entries as
needed.
[0] [1] [2] [3] [4] [5]
Swap? No.

58. 0
10
20
30
40
50
60
70
[1] [2] [3] [4] [5] [6]
The Bubble Sort Algorithm
• Loop over
array n-1
times,
swapping pairs
of entries as
needed.
[0] [1] [2] [3] [4] [5]
Swap? No.

59. 0
10
20
30
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50
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70
[1] [2] [3] [4] [5] [6]
The Bubble Sort Algorithm
• Continue
looping, until
done.
[0] [1] [2] [3] [4] [5]
Swap? Yes.