This document provides an overview of computational thinking and the Python programming language. It discusses computational thinking as a problem-solving process that involves decomposition, abstraction, pattern recognition, and algorithm design. It then defines Python as an interpreted, object-oriented programming language that is easy to use, cross-platform, and free. The document gives examples of computational thinking principles and walks through creating a simple Python program to calculate total marks from input subjects.

1. XI
Computer Science (083)
Board : CBSE
Unit -2:
Computational Thinking & Programming-1
Chapter-04
Basics of Computational Thinking

2. Unit -2
Computational Thinking & Programming
Prepared by
Devender Kumar
PGT(Comp.Sc)
JNV PURI,ODISHA

3. BASICS OF COMPUTATIONAL THINKING

4. Computational Thinking (CT) is a
problem solving process that includes a
number of characteristics and
dispositions. CT is essential to the
development of computer applications,
but it can also be used to support
problem solving across all disciplines,
including the humanities, math, and
science. Students who learn CT across
the curriculum can begin to see a
relationship between academic subjects,
as well as between life inside and outside
of the classroom.
BASICS OF COMPUTATIONAL THINKING

5. The Principles of Computational Thinking

6. The Principles of Computational Thinking
These are key techniques that
will help you think computationally
through a complex problem
(challenge, or task) before writing a
single line of code.
1
.
Decomposition
2
.
Abstraction
3
.
Pattern Recognition
4
.
Algorithm Design

7. The Principles of Computational Thinking
1. Decomposition
It is the breaking down a complex problem, data or
process into smaller, more manageable parts. In other
words the process of breaking down a big problem into a
set of smaller sub-process in order to understand a
problem or situation better, is known as decomposition.
For example:-
*Writing an essay is a complex task that can be broken
down into smaller task such as developing a thesis,
gathering evidence, and creating a bibliography page.
* Writing a computer program by determining a well-
defined series of small steps(modules) to solve the
problem or achieve a desired outcome

8. The Principles of Computational Thinking
2. Abstraction
Abstraction or Data Abstraction refers to focusing on
information relevant to a context/problem and
suppressing other details. Abstraction involves:-
Recognizing the context
Identifying the information relevant to the context
For example:-
*When we write a book report, we summarize and
discuss only theme or key aspects of the book, not each
context of book it is abstraction
* A calculator program only shows the numbers and
operators/functions buttons to user without giving details
of algorithm/program under it.

9. The Principles of Computational Thinking
3. Pattern Recognition
It refers to observing or looking for similarities or patterns among and
within small, decomposed problems; the indentified patterns help
solve more complex problems. It involves the following:-
Identifying similarities or common differences that lead us to
shortcuts.
 Using indentified shortcuts, mapping problem characteristics to
possible solutions.
*While driving on roads, the driver look for the patterns in traffic to
decide whether to switch lanes.
* Pattern recognition is required when categorizing rocks as either
igneous, metamorphic, or sedimentary.

10. The Principles of Computational Thinking
4. Algorithm Design
An algorithm is a sequence of steps that solves a problem by working
on some input data and producing desired outcomes(effective
solution). Algorithm design involves both creation and execution of
an algorithm.
For example:-
=>In programming algorithm can be:-
1. Decide the input variables.
2. Assign the value to the variables.
3. Checkout the conditions that can be apply on the variables.
4. Check True and False value of the condition
5. Perform operations on True and False values.
6. Exit the program.
=>In Daily Life when cook writes a recipe for a dish, he or she is
creating an algorithm that others can follow to replicate the dish.

11. PYTHON- AN PROGRAMMING LANGUAGE
Definition:-
The Python Language came in to existence in early 1990’s. It is not so
much popular such as C,C++,JAVA etc also it is not perfect for every
type of applications yet it has many advantages:-
1. Easy to use OO(Object Oriented) Language.
2. Expressive Language
3. Interpreted Languages
4. Cross-Platform Language
5. Free and Open Source
6. Variety of Usage/Applications
Some Minuses of Python are:-
1.Not the Fastest Language
2. Lesser Libraries than C,JAVA, Perl
3. Not Strong on Type-Binding(e.g If you declare variable as integer
but later on it can store string value in it.)
4. Not easily convertible From python to any other language.

12. PYTHON- AN PROGRAMMING LANGUAGE
Why it is called Python?
*When Mr. Guido van Rossum began implementing Python,
He was also reading the published scripts from
“Monty Python's Flying Circus”, a BBC comedy series from the
1970s. Van Rossum thought he needed a name that was
short, unique, and slightly mysterious, so he decided to call
the language Python
*Python is a widely used general-purpose, high level
programming language. It was created by Guido van Rossum
in 1991 and further developed by the Python Software
Foundation. It was designed with an emphasis on code
readability, and its syntax allows programmers to express
their concepts in fewer lines of code.

13. PYTHON- AN PROGRAMMING LANGUAGE
Working In Python
The python comes with Python Interpreter, Python IDLE(Integrated
Development Environment) and pip (package installer). To work in
Interactive as well as script mode, you need to open Python IDLE.
Steps to Open Python IDLE:-
Click on Start Button->All Program->Python->IDLE(python 3.8 ,32 bit)
It will open the following window:-

14. PYTHON- AN PROGRAMMING LANGUAGE
Writing a Program
'''PYTHON PROGRAM TO INPUT FIVE SUBJECT
AND FINDOUT THE TOTAL OF FIVE SUBJECTS''‘
e=int(input("ENTER VALUE OF FIRST SUB: "))
m=int(input("ENTER VALUE OF SECOND SUB: "))
s=int(input("ENTER VALUE OF THIRD SUB: "))
ss=int(input("ENTER VALUE OF FOURTH SUB: "))
c=int(input("ENTER VALUE OF FIVE SUB: "))
t=e+m+ss+c
print("The total mark is = ",t)

15. PYTHON- AN PROGRAMMING LANGUAGE
Output of the Program
ENTER VALUE OF FIRST SUB: 50
ENTER VALUE OF SECOND SUB: 70
ENTER VALUE OF THIRD SUB: 80
ENTER VALUE OF FOURTH SUB: 90
ENTER VALUE OF FIVE SUB: 60
The total mark is = 270

16. THANK YOU