C++ Literals 📝

Welcome to our lesson on C++ Literals! In this tutorial, we'll dive into understanding what literals are, why they are essential, and how to use them in your C++ programs. Let's get started!

What are Literals? 🎯

In simple terms, literals are specific values that are used to initialize variables or constants in a program. In C++, there are various types of literals, each representing different data types like integers, floating-point numbers, characters, and strings.

Integer Literals 💡

An integer literal is a sequence of digits representing an integer number. Here are some examples:

cpp

int myNum = 123; // decimal integer
int anotherNum = 0xABCD; // hexadecimal integer
int yetAnotherNum = 0123; // octal integer

📝 Note: When using hexadecimal or octal numbers, you must start the literal with 0x or 0, respectively.

Floating-Point Literals 💡

Floating-point literals represent decimal numbers with a fractional part. Here are some examples:

cpp

float pi = 3.14159; // decimal floating-point
double piValue = 3.14159265358979323846; // double precision floating-point

📝 Note: When initializing a float variable, use the float keyword. For double precision floating-point, simply omit the keyword.

Character Literals 💡

Character literals represent individual characters. In C++, character literals are enclosed in single quotes. Here's an example:

cpp

char myChar = 'A';

📝 Note: Character literals can also represent ASCII codes using their decimal values, like so:

cpp

char myCharCode = 65; // ASCII code for 'A'

String Literals 💡

String literals represent a sequence of characters, enclosed in double quotes. Here's an example:

cpp

std::string myString = "Hello, World!";

📝 Note: To create a multi-line string, enclose the string in triple double quotes.

Quiz 🎯

Now that you have a basic understanding of literals, let's move on to some practical examples.

Practical Examples 💡

Integer Example

cpp

#include <iostream>

int main() {
    int myNum = 123;
    int anotherNum = 0xABCD;
    int yetAnotherNum = 0123;

    std::cout << "Dec: " << myNum << std::endl;
    std::cout << "Hex: " << anotherNum << std::endl;
    std::cout << "Oct: " << yetAnotherNum << std::endl;

    return 0;
}

Floating-Point Example

cpp

#include <iostream>

int main() {
    float pi = 3.14159;
    double piValue = 3.14159265358979323846;

    std::cout << "Pi (float): " << pi << std::endl;
    std::cout << "Pi (double): " << piValue << std::endl;

    return 0;
}

Character Example

cpp

#include <iostream>

int main() {
    char myChar = 'A';
    char myCharCode = 65;

    std::cout << "Char: " << myChar << std::endl;
    std::cout << "Code: " << myCharCode << std::endl;

    return 0;
}

String Example

cpp

#include <iostream>
#include <string>

int main() {
    std::string myString = "Hello, World!";
    std::string multiLineString = R"(
    This is a multi-line string
    with multiple lines.
    )";

    std::cout << "String: " << myString << std::endl;
    std::cout << "Multi-line: " << multiLineString << std::endl;

    return 0;
}

That's it for today! With these examples, you should now have a solid understanding of literals in C++. In the next lesson, we'll dive into variables and data types.

Stay tuned! 🎯