Adina Institute Of Science And Technology Sagar Subject: - Basic Computer Engineering Code: - BT-205

Welcome to video Lecture

Adina Institute of Science & Technology Sagar
Program: B. Tech
Subject Name: Basic Computer Engineering
Subject Code: BT-205
Mr. Anurag Jain
Asst. Prof.
Department of Computer Science & Engineering
UNIT- 2

Introduction to Algorithms
1. Complexities and Flowchart.
2. Introduction to Programming, Categories of Programming Languages, ,
Programming Paradigms
3. Procedure Oriented Programming VS object oriented Programming.
4. Characteristics or Concepts of OOP.
5. Introduction to C++: Character Set, Tokens, Program Structure, Data
Types, Variables, Operators, Expressions, Statements and control structures,
I/O operations, Array, Functions,

Prepared By:- Mr. Anurag Jain Assit. Prof. Department of Computer Science & Engineering
Adina Institute Of Science And Technology Sagar Subject: - Basic Computer Engineering Code: - BT-205

Introduction to C++:
C++ history
C++ programming language was developed in 1980 by Bjarne Stroustrup at bell laboratories of
AT&T (American Telephone & Telegraph), located in U.S.A.
Bjarne Stroustrup is known as the founder of C++ language.
It was develop for adding a feature of OOP (Object Oriented Programming) in C without
significantly changing the C component.
C++ programming is "relative" (called a superset) of C, it means any valid C program is also a valid
C++ program.

C++ is a general-purpose programming language that was developed as an enhancement of the C

language to include object-oriented paradigm. It is an imperative and a compiled language.

Prepared By:- Mr. Anurag Jain Assit. Prof. Department of Computer Science & Engineering
Adina Institute Of Science And Technology Sagar Subject: - Basic Computer Engineering Code: - BT-205

C++ is a middle-level language it the advantage of programming low-level (drivers, kernels) and even
higher-level applications (games, GUI, desktop apps etc.). The basic syntax and code structure of both C
and C++ are the same.
Some of the features & key-points to note about the programming language are as follows:
 Simple: It is a simple language in the sense that programs can be broken down into logical units and parts,
has a rich library support and a variety of data-types.
 Machine Independent but Platform Dependent: A C++ executable is platform-dependent (compiled
programs on Linux won’t run on Windows), however they are machine independent.
 Mid-level language: It is a mid-level language as we can do both systems-programming (drivers,
kernels, networking etc.) and build large-scale user applications (Media Players, Photoshop, Game
Engines etc.)

 Structured programming language: C++ is a structured programming language in the sense that we can

break the program into parts using functions. So, it is easy to understand and modify.

 Rich library support: Has a rich library support (Both standard ~ built-in data structures, algorithms
etc.) as well 3rd party libraries (e.g. Boost libraries) for fast and rapid development.
 Pointer and direct Memory-Access: C++ provides pointer support which aids users to directly
manipulate storage address. This helps in doing low-level programming (where one might need to have
explicit control on the storage of variables).
 Memory Management: It supports the feature of dynamic memory allocation. In C++ language, we can
free the allocated memory at any time by calling the free () function.
 Speed
 The compilation and execution time of C++ language is fast.
 Pointer
 C++ provides the feature of pointers. We can directly interact with the memory by using the pointers. We
can use pointers for memory, structures, functions, array etc.
 Recursion
 In C++, we can call the function within the function. It provides code reusability for every function.
 Extensible
 C++ language is extensible because it can easily adopt new features.
 Object-Oriented: One of the strongest points of the language which sets it apart from C. Object-Oriented
support helps C++ to make maintainable and extensible programs. i.e. Large-scale applications can be
built.
 Compiled Language: C++ is a compiled language, contributing to its speed.

Prepared By:- Mr. Anurag Jain Assit. Prof. Department of Computer Science & Engineering
Adina Institute Of Science And Technology Sagar Subject: - Basic Computer Engineering Code: - BT-205

Applications of C++:
C++ finds varied usage in applications such as:
 Operating Systems & Systems Programming. e.g. Linux-based OS (Ubuntu etc.)
 Browsers (Chrome & Firefox)
 Graphics & Game engines (Photoshop, Blender, Unreal-Engine)
 Database Engines (MySQL, MongoDB, Redis etc.)
 Cloud/Distributed Systems.

Turbo C++ - Download & Installation

There are many compilers available for C++. You need to download any one. Here, we are going to
use Turbo C++. It will work for both C and C++. To install the Turbo C++ software, you need to follow
following steps.

1. Download Turbo C++

2. Create turboc directory inside c drive and extract the tc3.zip inside c:\turboc
3. Double click on install.exe file
4. Click on the tc application file located inside c:\TC\BIN to write the c program

C++ Program

Before starting the abcd of C++ language, you need to learn how to write, compile and run the first C++
program.

To write the first C++ program, open the C++ console and write the following code:

#include <iostream.h>
#include<conio.h>
void main()
{
clrscr();
cout << "Welcome to C++ Programming.";
getch();
}
#include<iostream.h> : includes the standard input output library functions. It
provides cin and cout methods for reading from input and writing to output respectively.

Prepared By:- Mr. Anurag Jain Assit. Prof. Department of Computer Science & Engineering
Adina Institute Of Science And Technology Sagar Subject: - Basic Computer Engineering Code: - BT-205

#include <conio.h> includes the console input output library functions. The getch() function is defined in
conio.h file.
void main() The main() function is the entry point of every program in C++ language. The void keyword
specifies that it returns no value.
cout << "Welcome to C++ Programming." is used to print the data "Welcome to C++
Programming." on the console.
getch() The getch() function asks for a single character. Until you press any key, it blocks (holds) the
screen.

1. Character Set: Character set is the combination of English language (Alphabets and White
spaces) and math‟s symbols (Digits and Special symbols). Character Set means that the characters and
symbols that a C++ Program can understand and accept. These are grouped to form the commands,
expressions, words, c-statements and other tokens for C++ Language.
Character Set is the combination of alphabets or characters, digits, special symbols and white spaces
same as learning English is to first learns the alphabets, then learn to combine these alphabets to form

Prepared By:- Mr. Anurag Jain Assit. Prof. Department of Computer Science & Engineering
Adina Institute Of Science And Technology Sagar Subject: - Basic Computer Engineering Code: - BT-205

words, which in turn are combined to form sentences and sentences are combined to form
paragraphs. More about a C++ program we can say that it is a sequence of characters. These
characters from the character set play the different role in different way in the C++ compiler. The
special characters are listed in Table

In addition to these characters, C++ also uses a combination of characters to represent special
conditions. For example. Character combinations such as „\nt, „\b‟ and „\t‟ are used to represent
newline, backspace and horizontal tab respectively.
When we have to learn English language we start from beginning as given below:
There are mainly four categories of the character
1. Alphabets
Alphabets are represented by A-Z or a-z. C/C++- Language is case sensitive so it takes different
meaning for small and upper case letters. By using this character set C/C++ statements and character
constants can be written very easily. There are total 26 letters used in programming.
2. Digits
Digits are represented by 0-9 or by combination of these digits. By using the digits numeric constant
can be written easily. Also numeric data can be assigned to the C/C++-tokens. There are total 10 digits
used in the C/C++-programming.
3. Special Symbols
All the keyboard keys except alphabet, digits and white spaces are the special symbols. These are
some punctuation marks and some special symbols used for special purpose.
There are total 30 special symbols used in the C/C++-programming. Special symbols are used for
C/C++-statements like to create an arithmetic statement +, -, * etc. to create relational statement <,
>, <=, >=, == etc. , to create assignment statement =, to create logical statement && etc. are
required.

Prepared By:- Mr. Anurag Jain Assit. Prof. Department of Computer Science & Engineering
Adina Institute Of Science And Technology Sagar Subject: - Basic Computer Engineering Code: - BT-205

4. White Spaces
White spaces has blank space, new line return, Horizontal tab space, carriage ctrl, Form feed etc. are
all used for special purpose. Also note that Turbo-C/C++ Compiler always ignores these white space
characters in both high level and low level programming.

2. Tokens: As we know that Software is a Program. And a Program is that which Contains set of
instructions, and an Instruction contains Some Tokens. So Tokens are used for Writing the
Programs the various Types of Tokens those are contained by the Programs.
As in the English language, in a paragraph all the words, punctuation mark and the blank spaces
are called Tokens. Similarly in a C++ program all the C++ statements having Keywords, Identifiers,
Constants, Strings, Operators and the Special Symbols are called C++ Tokens. C++ Tokens are the
essential part of a C++ compiler and so are very useful in the C++ programming. A Token is an
individual entity of a C++ program.
For example, some C++ Tokens used in a C++ program are:
Reserve: words long, do if, else etc.
Identifiers: Pay, salary etc.
Constant: 470.6,16,49 etc.
Strings: “Dinesh”, “2013-01” etc.
Operator: +, *, <, >=, &&,11, etc
Special symbols: 0, {}, #, @, %, etc.

3. Program Structure: The overall form of a program, with particular emphasis on the individual
components of the program and the interrelationships between these components. Programs are
frequently referred to as either well structured or poorly structured. With a well-structured program
the division into components follows some recognized principle such as information hiding, and the
interfaces between components are explicit and simple. By contrast, with a poorly structured
program the division into components is largely arbitrary (or even nonexistent), and interfaces are
implicit and complex.

4. Data Types: A data type specifies the type of data that a variable can store such as integer, floating,
character etc.

Prepared By:- Mr. Anurag Jain Assit. Prof. Department of Computer Science & Engineering
Adina Institute Of Science And Technology Sagar Subject: - Basic Computer Engineering Code: - BT-205

There are 4 types of data types in C++ language.

Types Data Types

Basic Data Type int, char, float, double, etc
Derived Data Type  array, pointer, Function
types Structure types
Union types
Enumeration Data Type enum
User Defined Data Type Class, structure, union, Enum,
Typedef

An enumeration is a data type that consists of a set of named values that represent integral
constants, known as enumeration constants.

Basic Data Types

The basic data types are integer-based and floating-point based. C++ language supports both signed
and unsigned literals.
The memory size of basic data types may change according to 32 or 64 bit operating system.

Let's see the basic data types. It size is given according to 32 bit OS.

Prepared By:- Mr. Anurag Jain Assit. Prof. Department of Computer Science & Engineering
Adina Institute Of Science And Technology Sagar Subject: - Basic Computer Engineering Code: - BT-205

Data Types Memory Size Range

char 1 byte -128 to 127
signed char 1 byte -128 to 127
unsigned char 1 byte 0 to 127
short 2 byte -32,768 to 32,767
signed short 2 byte -32,768 to 32,767
unsigned short 2 byte 0 to 32,767
int 2 byte -32,768 to 32,767
signed int 2 byte -32,768 to 32,767
unsigned int 2 byte 0 to 32,767
short int 2 byte -32,768 to 32,767
signed short int 2 byte -32,768 to 32,767
unsigned short int 2 byte 0 to 32,767
signed long int 4 byte
unsigned long int 4 byte
float 4 byte
double 8 byte
long double 10 byt
signed long int 4 byte

5. Variables: A variable is a name of memory location. It is used to store data. Its value can be
changed and it can be reused many times.
It is a way to represent memory location through symbol so that it can be easily identified.
Let's see the syntax to declare a variable:
type variable_list;
The example of declaring variable is given below:
int x;
float y;
char z;
Here, x, y, z are variables and int, float, char are data types.
We can also provide values while declaring the variables as given below:
int x=5,b=10; //declaring 2 variable of integer type
float f=30.8;
char c='A';

Prepared By:- Mr. Anurag Jain Assit. Prof. Department of Computer Science & Engineering
Adina Institute Of Science And Technology Sagar Subject: - Basic Computer Engineering Code: - BT-205

Rules for defining variables

A variable can have alphabets, digits and underscore.
A variable name can start with alphabet and underscore only. It can't start with digit.
No space is allowed within variable name.
A variable name must not be any reserved word or keyword e.g. char, float etc.
Valid variable names:
int a;
int _ab;
int a30;
Invalid variable names:
int 4;
int x y;
int double;

6. Operators:
An operator is simply a symbol that is used to perform operations. There can be many types of operations like
arithmetic, logical, bitwise etc.
There are following types of operators to perform different types of operations in C language.
 Arithmetic Operators
 Relational Operators
 Logical Operators
 Bitwise Operators
 Assignment Operator
 Unary operator
 Ternary or Conditional Operator

Prepared By:- Mr. Anurag Jain Assit. Prof. Department of Computer Science & Engineering
Adina Institute Of Science And Technology Sagar Subject: - Basic Computer Engineering Code: - BT-205

Category Operator Associativity

(संबद्धता)

Postfix () [] -> . ++ - - Left to right

Unary + - ! ~ ++ - - Right to left
(type)* & sizeof
Multiplicative */% Left to right
Additive +- Right to left
Shift << >> Left to right
Relational < <= > >= Left to right
Equality == !=/td> Right to left
Bitwise AND & Left to right
Bitwise XOR ^ Left to right
Bitwise OR | Right to left
Logical AND && Left to right
Logical OR || Left to right
Conditional ?: Right to left
Assignment = += -= *= /= Right to left
%=>>= <<= &= ^=
|=
Comma , Left to righ

Prepared By:- Mr. Anurag Jain Assit. Prof. Department of Computer Science & Engineering
Adina Institute Of Science And Technology Sagar Subject: - Basic Computer Engineering Code: - BT-205

7. Expressions:
C++ expression consists of operators, constants, and variables which are arranged according to the
rules of the language. It can also contain function calls which return values. An expression can
consist of one or more operands, zero or more operators to compute a value. Every expression
produces some value which is assigned to the variable with the help of an assignment operator.
Examples of C++ expression:
1. (a+b) - c
2. (x/y) -z
3. 4a2 - 5b +c
4. (a+b) * (x+y)
An expression can be of following
types:  Logical expressions

 Constant expressions

 Integral expressions

 Float expressions

 Pointer expressions

 Relational expressions

 Bitwise expressions
 Special assignment expressions

 Logical expressions

8. Statements and control structures,

Statements
Statements are fragments of the C++ program that are executed in sequence. The body of any
function is a sequence of statements. For example:
int main()
{
int n = 1; // declaration statement
n = n + 1; // expression statement
std::cout << "n = " << n << '\n'; // expression statement
return 0; // return statement
}

Prepared By:- Mr. Anurag Jain Assit. Prof. Department of Computer Science & Engineering
Adina Institute Of Science And Technology Sagar Subject: - Basic Computer Engineering Code: - BT-205

C++ includes the following types of statements:

1) Expression statements; An expression followed by a semicolon(;) is a statement.

2) Compound statements; Compound statements or blocks are brace-enclosed sequences of

statements. When one statement is expected, but multiple statements need to be executed in
sequence (for example, in an if statement or a loop), a compound statement may be used:

if (x > 5) // start of if statement

{ // start of block
int n = 1; // declaration statement
std::cout << n; // expression statement
} // end of block, end of if statement

3) Selection statements; Selection statements choose between one of several flows of control.

1) if statement;
2) if statement with an else clause;
3) switch statement.

4) Iteration statements; Iteration statements repeatedly execute some code.

1) while loop; while ( condition ) statement
2) do-while loop; do statement while ( expression ) ;
3) for loop; for ( init-
statement condition(optional) ; expression(optional) ) statement
4) range for loop. for ( for-range-decl : for-range-init ) statement

5) Jump statements; Jump statements unconditionally transfer flow control

1) break statement;
2) continue statement;
3) return statement with an optional expression;
4) return statement using list initialization;
5) goto statement.

Control structures
Control Structures are just a way to specify flow of control in programs. Any algorithm or program
can be clearer and understood if they use self-contained modules called as logic or control
structures. It basically analyzes and chooses in which direction a program flows based on certain
parameters or conditions.

Prepared By:- Mr. Anurag Jain Assit. Prof. Department of Computer Science & Engineering
Adina Institute Of Science And Technology Sagar Subject: - Basic Computer Engineering Code: - BT-205

 Sequential: default mode. Sequential execution of code statements (one line after another) -- like following

a recipe
 Selection: used for decisions, branching -- choosing between 2 or more alternative paths. In C++, these
are the types of selection statements:
 if

 if/else

 switch

 Repetition: used for looping, i.e. repeating a piece of code multiple times in a row. In C++, there are
three types of loops:
 while

 do/while

 for

The function construct, itself, forms another way to affect flow of control through a whole program.

The most common selection statement is the if/else statement.

Basic syntax:
if (expression)
statement
else
statement
The else clause is optional, so this format is also legal:
if (expression)
statement
Examples
1. if (grade >= 68)
cout << "Passing";
// Notice that there is no else clause. If the grade is below 68, we move on.
2. if (x == 0)
cout << "Nothing here";
else
cout << "There is a value";
// This example contains an else clause. The bodies are single statements.

Prepared By:- Mr. Anurag Jain Assit. Prof. Department of Computer Science & Engineering
Adina Institute Of Science And Technology Sagar Subject: - Basic Computer Engineering Code: - BT-205

3. A switch statement is often convenient for occasions in which there are multiple cases to
choose from.
The syntax format is:
switch (expression)
{
case constant:
statements
case constant:
statements

... (as many case labels as needed)

default: // optional label

statements
}

9. I/O operations,
What is input?
 Information given to the program, is called input
 In input data is flow inside the program
 It required a source(for reading )
stadin - - > standard input used as scanf function.
stdout ---> standard input used as printf function taken by monitor(gives destination)
What is output?
 Information given by the program is called output
 In output data is flow outside the program
 In c++ I/O operations are alone using streams
 A stream is class is provide set of functions to perform input and output operations
 A stream represents input source (reading) and output destination (writing)
 C++ provides 2 stream classes
1. ostream
2. istream
 Istream The istream consists of input functions to read streams of characters from the keyboard.
 Ostream The ostream consists of output functions to write a character onto the screen.

Prepared By:- Mr. Anurag Jain Assit. Prof. Department of Computer Science & Engineering
Adina Institute Of Science And Technology Sagar Subject: - Basic Computer Engineering Code: - BT-205

10. Array :
Like other programming languages, array in C++ is a group of similar types of elements that have
contiguous memory location.
In C++ std::array is a container that encapsulates fixed size arrays. In C++, array index starts from 0.
We can store only fixed set of elements in C++ array.

Advantages of C++ Array

 Code Optimization (less code)

 Random Access

 Easy to traverse data

 Easy to manipulate data

 Easy to sort data etc.

Disadvantages of C++ Array

 Fixed size

Prepared By:- Mr. Anurag Jain Assit. Prof. Department of Computer Science & Engineering
Adina Institute Of Science And Technology Sagar Subject: - Basic Computer Engineering Code: - BT-205

C++ Array Types

There are 2 types of arrays in C++ programming:
1. Single Dimensional Array
2. Multidimensional Array

Arrays can be single or multidimensional. The number of subscript or index determines the
dimensions of the array. An array of one dimension is known as a one-dimensional array or 1-D
array, while an array of two dimensions is known as a two-dimensional array or 2-D array.

One-dimensional array
Conceptually you can think of a one-dimensional array as a row, where elements are stored one after
another.

Syntax: datatype array_name[size];

datatype: It denotes the type of the elements in the array.
array_name: Name of the array. It must be a valid identifier.
size: Number of elements an array can hold. Here is some example of array declarations:

1 int num[100];

2 float temp[20];

3 char ch[50];

Prepared By:- Mr. Anurag Jain Assit. Prof. Department of Computer Science & Engineering
Adina Institute Of Science And Technology Sagar Subject: - Basic Computer Engineering Code: - BT-205

num is an array of type int, which can only store 100 elements of type int.
temp is an array of type float, which can only store 20 elements of type float.
ch is an array of type char, which can only store 50 elements of type char.

Two-dimensional Array
The syntax declaration of 2-D array is not much different from 1-D array. In 2-D array, to declare and
access elements of a 2-D array we use 2 subscripts instead of 1.
Syntax: datatype array_name[ROW][COL];
The total number of elements in a 2-D array is ROW*COL.
Let’s take an example.
int arr[2][3];
This array can store 2*3=6 elements. You can visualize this 2-D array as a matrix of 2 rows and 3
columns.

The individual elements of the above array can be accessed by using two subscript instead of one. The
first subscript denotes row number and second denotes column number. As we can see in the above
image both rows and columns are indexed from 0. So the first element of this array is at arr[0][0] and
the last element is at arr[1][2].
Here is how you can access all the other elements:
arr[0][0] - refers to the first element
arr[0][1] - refers to the second element
arr[0][2] - refers to the third element
arr[1][0] - refers to the fourth element

Prepared By:- Mr. Anurag Jain Assit. Prof. Department of Computer Science & Engineering
Adina Institute Of Science And Technology Sagar Subject: - Basic Computer Engineering Code: - BT-205

arr[1][1] - refers to the fifth element

arr[1][2] - refers to the sixth element

11. Functions
The function in C++ language is also known as procedure or subroutine in other programming
languages.
To perform any task, we can create function. A function can be called many times. It provides
modularity and code reusability
A function is a block of code which only runs when it is called. You can pass data, known as
parameters, into a function. Functions are used to perform certain actions, and they are important for
reusing code: Define the code once, and use it many times.

Create a Function
C++ provides some pre-defined functions, such as main(), which is used to execute code. But you can also
create your own functions to perform certain actions.
To create (often referred to as declare) a function, specify the name of the function, followed by
parentheses ():
Syntax
void myFunction() {
// code to be executed
}

Example Explained
 myFunction() is the name of the function
 void means that the function does not have a return value.
 inside the function (the body), add code that defines what the function should do.
Advantage of functions
There are many advantages of functions.
1) Code Reusability
By creating functions in C++, you can call it many times. So we don't need to write the same code again
and again.
2) Code optimization

Prepared By:- Mr. Anurag Jain Assit. Prof. Department of Computer Science & Engineering
Adina Institute Of Science And Technology Sagar Subject: - Basic Computer Engineering Code: - BT-205

It makes the code optimized; we don't need to write much code. Suppose, you have to check 3 numbers (531,
883 and 781) whether it is prime number or not. Without using function, you need to write the prime
number logic 3 times. So, there is repetition of code.
But if you use functions, you need to write the logic only once and you can reuse it several times.
Types of Functions
There are two types of functions in C++ programming:
1. Library Functions: are the functions which are declared in the C++ header files such as ceil(x), cos(x),
exp(x), etc.
2. User-defined functions: are the functions which are created by the C++ programmer, so that he/she can
use it many times. It reduces complexity of a big program and optimizes the code.

Prepared By:- Mr. Anurag Jain Assit. Prof. Department of Computer Science & Engineering
Adina Institute Of Science And Technology Sagar Subject: - Basic Computer Engineering Code: - BT-205

C is a procedural programming C++ is a Object-Oriented

language. Programming language.

C follows Top Down C++ follows Bottom Up programming

programming approach approach.
The extension of a C program file The extension of a c+ + program
is .c language is .cpp
C is a function driven language. C++ is an object driven language.
In C, structure does not support While, in C++ structure provides the
declaring of function as its feature of declaring a function as a
member member function.
In C scanf and printf functions In C++ cin and cout objects are for
are used for standard input and standard input and output operations.‬‬
output operation
C is not compatible with another C++ is compatible with the other
language. generic programming languages.
In C, the variable should be C++ allows you to declare variables
defined at the beginning of the anywhere in the function.
program.
Does not support encapsulation. Supports encapsulation. Data and
As Data and functions are functions are encapsulated together
separate and free entities. as an object.
C provide malloc() and calloc() C++ provides a new operator for this
functions for dynamic memory purpose.
allocation.
In C, Inheritance is not Inheritance is possible in C++
supported. language.
Contain 32 keywords. Contains 52 keywords.
Polymorphism is not possible Polymorphism is one of the most
Important Features of OOPS.

Prepared By:- Mr. Anurag Jain Assit. Prof. Department of Computer Science & Engineering
Adina Institute Of Science And Technology Sagar Subject: - Basic Computer Engineering Code: - BT-205

C is a procedural programming C++ is a Object-Oriented Prog. Lang.

lang

Prepared By:- Mr. Anurag Jain Assit. Prof. Department of Computer Science & Engineering