C++ Data Types

Introduction

Data types in C++ define the type of data that a variable can hold. Understanding the different data types is essential for effective programming, as it helps in choosing the appropriate type for the data you want to store and manipulate. This chapter will cover the basic data types in C++ with simple examples and their outputs.

Categories of Data Types

C++ data types can be categorized into:

1. Integer Types
2. Floating-Point Types
3. Character Type
4. Boolean Type
5. Wide Character Type

Integer Types

int

The int type is used to store whole numbers.

Example

#include <iostream>
using namespace std;

int main() {
    int age = 25; // Declare an integer variable and initialize it
    cout << "Age: " << age << endl; // Output the value of age
    return 0;
}

Output

Age: 25

short

The short type is used to store short integer values, typically smaller range than int.

Example

#include <iostream>
using namespace std;

int main() {
    short year = 2022; // Declare a short integer variable and initialize it
    cout << "Year: " << year << endl; // Output the value of year
    return 0;
}

Output

Year: 2022

long

The long type is used to store long integer values, typically larger range than int.

Example

#include <iostream>
using namespace std;

int main() {
    long population = 7800000000; // Declare a long integer variable and initialize it
    cout << "Population: " << population << endl; // Output the value of population
    return 0;
}

Output

Population: 7800000000

long long

The long long type is used to store very large integer values.

Example

#include <iostream>
using namespace std;

int main() {
    long long distance = 150000000000LL; // Declare a long long integer variable and initialize it
    cout << "Distance: " << distance << endl; // Output the value of distance
    return 0;
}

Output

Distance: 150000000000

Floating-Point Types

float

The float type is used to store single-precision floating-point numbers.

Example

#include <iostream>
using namespace std;

int main() {
    float pi = 3.14f; // Declare a float variable and initialize it
    cout << "Pi: " << pi << endl; // Output the value of pi
    return 0;
}

Output

Pi: 3.14

double

The double type is used to store double-precision floating-point numbers.

Example

#include <iostream>
using namespace std;

int main() {
    double gravity = 9.81; // Declare a double variable and initialize it
    cout << "Gravity: " << gravity << endl; // Output the value of gravity
    return 0;
}

Output

Gravity: 9.81

long double

The long double type is used to store extended precision floating-point numbers.

Example

#include <iostream>
using namespace std;

int main() {
    long double precision = 1.123456789012345L; // Declare a long double variable and initialize it
    cout << "Precision: " << precision << endl; // Output the value of precision
    return 0;
}

Output

Precision: 1.12346

Character Type

char

The char type is used to store single characters.

Example

#include <iostream>
using namespace std;

int main() {
    char initial = 'A'; // Declare a char variable and initialize it
    cout << "Initial: " << initial << endl; // Output the value of initial
    return 0;
}

Output

Initial: A

Boolean Type

bool

The bool type is used to store boolean values (true or false).

Example

#include <iostream>
using namespace std;

int main() {
    bool isStudent = true; // Declare a bool variable and initialize it
    cout << "Is Student: " << isStudent << endl; // Output the value of isStudent
    return 0;
}

Output

Is Student: 1

(Note: true is output as 1 and false as 0.)

Wide Character Type

wchar_t

The wchar_t type is used to store wide characters, which are typically used for Unicode characters.

Example

#include <iostream>
using namespace std;

int main() {
    wchar_t wideChar = L'?'; // Declare a wide char variable and initialize it
    wcout << L"Wide Character: " << wideChar << endl; // Output the value of wideChar
    return 0;
}

Output

Wide Character: ?

Conclusion

Understanding C++ data types is fundamental to effective programming. By knowing the different data types and their usage, you can store and manipulate data efficiently. This chapter covered the basic data types, including integer, floating-point, character, boolean, and wide character types. In the next chapter, we will delve into more advanced topics such as C++ constants and literals.