Integer Variable in C++ Programming with Examples
C++ Basic Concepts
In this lesson, we will learn about the Integer Variable in C++ programming language. We will go through some examples of it and a quiz on it.
Integer Type Variable
In our earlier lesson we have learned about variable and how they are used to store values in computer memory. Now in this lesson we will learn how to declare variable in C++ programming using an Integer Data Type.
So the first type of variable we need to know about is of type int - short for integer. This type of variable is used to store a whole number either positive or negative only (example: 10, 89, -24 etc). But if you try to store a fractional value (example: 12.36) in it then it will only store the integer part 12 but not the decimal part 36.
The memory storage capacity of an integer variable is 4 bytes and the range of an int variable is between -2,147,483,648 to 2,147,483,647.
Syntax of Declaring Integer Variable in C++
Here int is used for declaring Integer data type and variable_name is the name of variable (you can use any name of your choice for example: a, b, c, alpha, etc. but remember the Naming Conventions while declaring an integer variable) and ; is used for line terminator (end of line).
Now let's see some examples for more understanding.
Declare a signed integer variable x.
signed int x;
Note: In C++ programming there is no need to write signed data type modifier as because it is the default modifier of int and char data type if no modifier is specified.
Declare an integer variable x to assign an integer value 10.
int x = 10;
Declare 3 integer variables x, y and z in a single line.
int x, y, z;
Declare 3 integer variables x, y and z to assign the integer value 42, 67 and 85 respectively in a single line.
int x=42, y=67, z=85;
Declare an integer variable x and assign the integer value 18 in the second line.
int x; x = 18;
Declare an integer variable x and assign the integer value 76 and change its value to 54 in the next line.
int x = 76; x = 54; // now the new value of x is 54
Declare a short integer variable x and assign the value 9432.
short int x = 9432;
A short integer variable can store numbers between range -32,768 to 32,767.
Declare 2 unsigned integer variables x, y and assign the value 7645 and 24861 respectively.
unsigned int x = 7645, y=24861;
An unsigned integer variable can store only positive numbers between range 0 to 4,294,967,295.
Declare an integer variable x with a long long data type modifier and assign the value 9832567.
long long int x = 9832567;
Test Your Knowledge
Attempt the multiple choice quiz to check if the lesson is adequately clear to you.