This is a presentation on C language. Brief description on C language Topics Covered What is C Header files in C What is main function in c Basic Structure of C Keywords & Identifiers Data Types & Variable Declaration in C Includes | Format Specifier | Memory Size Input in C (printf() scanf() function) Operators in C: Asthmatics,Increment Decrement, Relational, Logical operators Sample Exercise LinkedIn: https://www.linkedin.com/in/shamsulhusainansari/ GitHub: https://github.com/shamsulhusainansari

1. Basics of ‘C’
Programming
Presented By: Shamsul Husain Ansari
G. H. Raisoni Institute of Engineering & Technology, Nagpur

2. What is ‘C’?
C is a Procedure Oriented Programming language use for Game design,
Graphics, Enterprise Applications.
C is widely used language. It provides many features that are given below.
● Machine Independent
● High Speed
● Pointers
● Recursion

3. Header Files : Header files in C language Contains the set of predefined standard
library functions.
● #include<stdio.h> : It is used for perform input and output operations using
functions scanf() and printf().
● #include<math.h>: It is used to perform mathematical operations like sqrt(),
pow(), etc.
● #include<time.h>: It is used to perform functions related to date() and time().
● #include<fstream.h>: It is used to control the data to read from a file as an
input and data to write into the file as an output
● Example : #include<stdio.h>
Header files in ‘C’.

4. What is main in ‘C’.
A main is a predefined keyword or function in C. It is a special function that always starts
executing code from the ‘main’ having ‘int’ or ‘void’ as return data type. In other words, a main()
function is an entry point of the programming code to start its execution.
Syntax:
int main() {
//body of the code
return 0;
}

5. Basic Structure of C Program
Header file #include<stdio.h>
main function int main() {
Variable declaration int a=20;
Body printf(“The value of a is %d”,a);
return return 0;
}

6. Keywords & Identifiers in ‘C’
In C language identifiers are the names given to variables, constants, functions and user-
defined data.
Syntax : data_type variable_name;
Examples: int marks; //in Ram the 2 byte of memory allocate by the name of marks.
Keyword Identifier
Int
float
char
number
decimal
character

7. Data Types in ‘C'
C has various data types to store data in program. C program can store integer,
decimal number, character(alphabets), string(word or sentence), list etc.
Syntax : type variable_name;
Example1: int roll_no; // int used for storing integer value.
Example 2: float percentage; // float data type used for storing decimal
numbers.
Note: C is a case sensitive language. It matter whether an identifier such as variable
name, is UPPERCASE or lowercase.

8. Keyword Used Format Specifier Size (Bytes)
int “%d” 4
char “%c” 1
float “%f” 4
double “%lf” 8
The format specifiers are used in C for input and output purposes. Using this concept the compiler
can understand that what type of data is in a variable during taking input using scanf() function and
printing using printf() function.

9. C Input
In C programming, scanf() is one of the commonly used function to take input from the user.
The scanf() function read formatted input from the standard input such as keyboards.
Example:
#include<stdio.h>
int main() {
int age; // variable declaration of type integer.
char name[7];
scanf(“%d”, &age);
scanf(“%s”,name);
printf(“Age= %d”, age); // printf() function used to display the output to
the user.
return 0;
}
Note: & represent the memory address and &age denotes the memory address of age.

10. Operators in C
An operator is simply a symbol that is used to perform operations. There can be many type of
operations like arithmetic, logical, bitwise, etc.
Arithmetic Operator: An arithmetic operator perform mathematical operation such as addition,
subtraction, multiplication, division etc on numerical values.
Operator Meaning of Operator
+ Addition
- subtraction
* multiplication
/ division
& remainder after division (modulo division)

11. Example
#include<stdio.h>
int main() {
Int a = 6, b = 4, c;
c = a+b;
printf(“ADDITION: %d”,c);
c = a-b;
printf(“SUBTRACTION: %d”, c);
return 0;
}
Output: ADDITION: 10
SUBTRACTION: 2

12. Increment & Decrement Operators
C programming has two operator increment ++ and decrement - - to change the
value of an operand (constant or variable) by 1.
Operator Meaning of Operator
++ Increment the value by 1
– – Decrement the value by 1
#include<stdio.h>
int main() {
int a = 10, b = 5;
printf(“INCREMENT: %d”,++a);
printf(“DECREMENT: %d”, - - b );
return 0;
}

13. Relational Operators
A relational operator checks the relationship between two operands. If the relation
is true, it returns 1; if the relation is false, it return value 0.
Operator Meaning of Operator Example
== Equal to 5 == 3 return 0
> Greater than 5 > 3 return 1
< Less than 5 < 3 return 0
!= Not equal to 5!=3 return 1
>= Greater than or equal to 5>=3 return 1
<= Less than or equal to 5<=3 return 0

14. Example
#include<stdio.h>
int main() {
Int a = 5, b = 3;
printf(“Equal to: %d”, a==b);
printf(“Not Equal: %d”, a!=b);
return 0;
}
Output: Equal to: 0
Not Equal : 1

15. Logical Operators
An expression containing logical operator returns either 0 or 1 depending upon
whether expression results true or false. Logical operators are commonly used in
decision making in C Programming
Operator Meaning
&& Logical AND. True only if all the operand
are true.
|| Logical OR. True only if either one operand
is true.
! Logical NOT. Only if the operand is 0

16. Example
#include<stdio.h>
int main() {
int a = 5, b = 5, c=10, result;
result = (a == b) && (c > b);
printf("%dn", result);
result = (a != b) || (c > b);
printf("%dn", result);
result = !(a == b);
printf("%dn", result);
return 0;
}

17. Exercise
Char type
Integer type
Float type

18. Solution