Mastering Data Types in C++: A Comprehensive Guide with Codes and Examples (2023)

Article by: Manish Methani

Last Updated: October 22, 2021 at 8:04am IST
5 min 2 sec read

Data types are a fundamental concept in programming languages, including C++. A data type is a classification of data items that tells the compiler how to interpret the data. In C++, data types are used to define variables, which are used to store values in memory. In this tutorial, we will explore the various data types in C++, including built-in data types and user-defined data types.

Built-in Data Types:

C++ provides several built-in data types, including:

1. Integer Types: Used for storing integer values. There are four integer types in C++:

• char: 1 byte
• short: 2 bytes
• int: 4 bytes
• long: 8 bytes

Here's an example of declaring integer variables:

char my_char = 'a';
short my_short = 42;
int my_int = 12345;
long my_long = 123456789;

        2. Floating-Point Types: Used for storing decimal values. There are two floating-point types in C++:

• float: 4 bytes
• double: 8 bytes

Here's an example of declaring floating-point variables:

float my_float = 3.14;
double my_double = 3.14159265359;

   3. Boolean Type: Used for storing true or false values.

bool my_bool = true;

   4. Void Type: Used for indicating that a function returns no value.

void my_function() {
    // do something
}

In C++, user-defined data types allow programmers to create custom data types that suit their specific needs. These data types are defined by the programmer and can be used just like any other built-in data type in C++. In this tutorial, we'll cover the basics of creating and using user-defined data types in C++.

Defining a User-Defined Data Type

To define a user-defined data type in C++, we use the struct keyword. The struct keyword allows us to create a group of related variables that can be treated as a single entity. Here's an example:

struct Person {
    string name;
    int age;
    float height;
};

In this example, we've defined a Person struct that contains three variables: name, age, and height. This struct can now be used to create instances of a Person object:

Person john;
john.name = "John Smith";
john.age = 30;
john.height = 5.8;

Using a User-Defined Data Type

Once we've defined a user-defined data type, we can use it just like any other data type in C++. Here's an example of how we might use the Person struct we defined earlier:

#include <iostream>
using namespace std;

struct Person {
    string name;
    int age;
    float height;
};

int main() {
    Person john;
    john.name = "John Smith";
    john.age = 30;
    john.height = 5.8;

    cout << "Name: " << john.name << endl;
    cout << "Age: " << john.age << endl;
    cout << "Height: " << john.height << endl;

    return 0;
}

In this example, we've included the Person struct in our main function and created an instance of a Person object called john. We then set the values of john's name, age, and height variables and printed them out using cout.

Benefits of User-Defined Data Types

Using user-defined data types can provide several benefits to programmers. One of the main benefits is that they allow programmers to create custom data types that are tailored to their specific needs. This can make code more readable and easier to understand, as the custom data types can be given names that describe their purpose.

Another benefit is that user-defined data types can help to organize code by grouping related variables together. This can make it easier to maintain and modify code in the future, as changes can be made to the data type rather than having to modify individual variables throughout the code.

Conclusion

In this tutorial, we've covered the basics of creating and using user-defined data types in C++. We've seen how to define a struct to create a custom data type, and how to use that data type to create instances of objects. We've also discussed the benefits of using user-defined data types in programming. With these tools, programmers can create more efficient and effective code that is easier to understand and maintain.