Introduction to C++ | Variables

C++ Variables

In C++, variables are used to store data that can be referenced and manipulated during the program's execution. Every variable in C++ has a specific type that defines what kind of data it can store, such as integers, floating-point numbers, or characters.

What is a Variable?

A variable in C++ is a named location in memory that stores a value. Each variable is associated with a data type that determines what kind of value it can hold. The value of a variable can change during the program’s execution.

Declaring a Variable

To declare a variable in C++, you need to specify its data type followed by the variable's name. For example:

int age;

In this example, we declared a variable named age of type int to store integer values.

Types of Variables

C++ supports several types of variables. The most common types include:

1. Integer Variables

• int: Used to store integers (whole numbers).
• short: Short integer type, typically uses less memory than int.
• long: Long integer type, typically uses more memory than int.
• long long: Larger integer type.

2. Floating-Point Variables

• float: Used to store single-precision floating-point numbers (numbers with decimals).
• double: Used to store double-precision floating-point numbers, offering more precision than float.
• long double: Used to store extended precision floating-point numbers.

3. Character Variables

• char: Used to store a single character or symbol.

4. Boolean Variables

• bool: Used to store Boolean values, either true or false.

5. String Variables

• string: Used to store sequences of characters (text).

Initializing a Variable

Variables can be initialized (assigned an initial value) at the time of declaration. For example:

int age = 25;

This initializes the age variable with the value 25.

Code Example: Using Variables

Here's an example of how variables can be declared, initialized, and used in a C++ program:

                #include <iostream>
                using namespace std;
        
                int main() {
                    // Declare and initialize variables
                    int age = 25;
                    float height = 5.9;
                    char grade = 'A';
                    bool isStudent = true;
        
                    // Output the values of variables
                    cout << "Age: " << age << endl;
                    cout << "Height: " << height << endl;
                    cout << "Grade: " << grade << endl;
                    cout << "Is Student: " << isStudent << endl;
        
                    return 0;
                }
                    

Output

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