VARIABLES DATA TYPES

1. C++ Language
By:-AAKASH KAUSHIK
#9289817971, 98919893083
Email-theaakashkumar@gmail.com

2. UNIT -3
VARIABLES & DATA
TYPES

3. VARIABLES
Variables are used to store values.
Variables are name of storage location where
data of particular type can be stored.
Variables stores the latest updated value.
We can use any valid Identifier as a variable
name.
AAKASH KAUSHIK
9891983083,9289817971

4. DECLARATION OF VARIABLES
Declaration syntax:-
Datatype variablename;
Where data type could be any valid Data type for
ex.- int, char, float, etc. and variable name could be
any valid identifier.
For ex.
int a;
char b;
float c;
AAKASH KAUSHIK
9891983083,9289817971

5. INTIALIZATION OF VARIABLES
Intialization means assigning value to declared
variable.
For ex:-
a=10;
b=‘A’;
c=3.14;
AAKASH KAUSHIK
9891983083,9289817971

6. MORE ON DECLARATION AND
INTIALIZATION
Declaration and initialization can take place in
same statement also.
For ex.:-
int a=10;
We can declare more than one variable of same
in a single statement separated by comma
For ex.:-
int a,b,c;
AAKASH KAUSHIK
9891983083,9289817971

7. Program of sum of 2 variables
#include<iostream.h>
#include<conio.h>
void main()
{
clrscr();
int a,b,sum;
a=10;
b=20;
sum=a+b;
cout<<“value of first number”;
cout<<a; // syntax to display value of a variable
cout<<“value of second number”;
cout<<b;
cout<<“sum of numbers”;
cout<<sum;
getch();
AAKASH KAUSHIK
}
9891983083,9289817971

8. STATIC V/S DYNAMIC INTIALIZATION
Static initialialization means when value of
variable is already known and static initialization
takes place at compile time.
For ex. int a=10;
Dynamic initialization means when value of a
variable is decided at run time i.e., inside
execution
For dynamic initialization we use CIN
AAKASH KAUSHIK
9891983083,9289817971

9. SAMPLE PROGRAM OF DYNAMIC
INTIALIZATION
//PROGRAM TO FIND AREA OF A CIRCLE
#include<iostream.h>
#include<conio.h>
void main()
{
clrscr();
float r,area;
cout<<“enter radius of circle”;
cin>>r; //here value of r will be demanded at runtime
area=3.14*r*r;
cout<<“area of circle”;
cout<<area;
getch();
AAKASH KAUSHIK
}
9891983083,9289817971

10. Cascading of input output statements
We can combine multiple input and output
statements into a single one.
For ex.:-
int a,b,sum;
cout<<“enter 2 numbers”;
cin>>a>>b;
sum=a+b;
cout<<“Sum of ”<<a<<“ & ”<<b<<“is ”<<sum;
AAKASH KAUSHIK
9891983083,9289817971

11. DATA TYPES
 Data type is a data storage format that can
contain a specific type or range of values.
 When computer programs store data in
variables, each variable must be assigned a
specific data type.
 Data types represents the type of information
that can be stored in a variable.
 Data types are the keywords, which are used
for Assigning a type to a variable.
AAKASH KAUSHIK
9891983083,9289817971

12. INTEGER DATA TYPES
AAKASH KAUSHIK
9891983083,9289817971

13. FLOAT/REAL DATA TYPES
AAKASH KAUSHIK
9891983083,9289817971

14. CHARACTER DATA TYPES
AAKASH KAUSHIK
9891983083,9289817971

15. EXERCISE
Write a program to calculate sum, difference,
product, division of two numbers.
Write a program to find area and perimeter of
a rectangle.
Write a program to calculate area and
circumference of a circle.
Write a program to swap two numbers using
third variable.
Write a program to swap two numbers
without using third variable.
AAKASH KAUSHIK
9891983083,9289817971

16. EXERCISE
Write a program to take input marks of 5
subjects and calculate total marks and
average marks.
Write a program to calculate simple interest.
Write programs to convert temperature
entered into Fahrenheit to Celsius and Celsius
to Fahrenheit.
f=(c*9/5)+32
c=(f-32)*5/9
AAKASH KAUSHIK
9891983083,9289817971

17. THANK
YOU
AAKASH KAUSHIK
9891983083,9289817971