Short long and unsigned modifiers in C++

The provided C++ code demonstrates the declaration and usage of various fundamental data types and their sizes.

Code

#include <iostream>
using namespace std;

/**
 * @brief Main function demonstrating the use of various data types in C++ and their sizes.
 *
 * This program declares variables of different data types including integer types
 * (int, short int, long int, unsigned int, unsigned short int, unsigned long int),
 * character types (char, unsigned char, signed char),
 * and floating-point types (float, double, long double).
 * It then prints the size of each data type in bytes.
 *
 * @return int Returns 0 upon successful execution.
 */
int main() {
    
    // Integer types
    int Integer; // Range: -2147483648 to 2147483647
    short int shortInteger; // Range: -32768 to 32767
    long int longInteger; // Range: -9223372036854775808 to 9223372036854775807
    unsigned int unsignedInteger; // Range: 0 to 4294967295
    unsigned short int unsignedShortInteger; // Range: 0 to 65535
    unsigned long int unsignedlongInteger; // Range: 0 to 18446744073709551615

    // Character types
    char normalChar; // Range: -128 to 127
    unsigned char unsignedChar; // Range: 0 to 255
    signed char signedCchar; // Range: -128 to 127 (same as char)

    // Floating-point types
    float normalFloat; // Range: 1.4012984643248171e-45 to 3.4028234663852886e+38
    double normalDouble; // Range: 2.2250738585072014e-308 to 1.7976931348623157e+308
    long double normalLongDouble; // Range: 2.2250738585072014e-308 to 1.7976931348623157e+308

    // Printing the size of each data type
    cout <<"The size of int is " <<sizeof(Integer) << " bytes" << endl;
    cout <<"The size of short int is " <<sizeof(shortInteger) << " bytes" << endl;
    cout <<"The size of long int is " <<sizeof(longInteger) << " bytes" << endl;
    cout <<"The size of unsigned int is " <<sizeof(unsignedInteger) << " bytes" << endl;
    cout <<"The size of unsigned short int is " <<sizeof(unsignedShortInteger) << " bytes" << endl;
    cout <<"The size of unsigned long int is " <<sizeof(unsignedlongInteger) << " bytes" << endl;
    cout <<"The size of char is " <<sizeof(normalChar) << " bytes" << endl;
    cout <<"The size of unsigned char is " <<sizeof(unsignedChar) << " bytes" << endl;
    cout <<"The size of signed char is " <<sizeof(signedCchar) << " bytes" << endl;
    cout <<"The size of float is " <<sizeof(normalFloat) << " bytes" << endl;
    cout <<"The size of double is " <<sizeof(normalDouble) << " bytes" << endl;
    cout <<"The size of long double is " <<sizeof(normalLongDouble) << " bytes" << endl;

    return 0;
}

Explanation

The provided C++ code demonstrates the declaration and usage of various fundamental data types and their sizes. It begins by including the <iostream> header, enabling input and output operations, and uses the std namespace to avoid prefixing standard library entities with std::.

The main function, which is the entry point of the program, declares variables of different data types, including integer types (int, short int, long int, unsigned int, unsigned short int, unsigned long int), character types (char, unsigned char, signed char), and floating-point types (float, double, long double). Each variable is accompanied by a comment indicating its range, which is crucial for understanding the limits of each data type.

For example, the integer variable declaration is shown as follows:

int Integer; // Range: -2147483648 to 2147483647

This line declares an int variable named Integer, which can store values from -2,147,483,648 to 2,147,483,647.

After declaring these variables, the program prints the size of each data type in bytes using the sizeof operator. This is a compile-time operator that determines the size, in bytes, of a variable or data type. The output is directed to the console using cout, which is part of the iostream library.

For instance, the size of the int data type is printed with the following line:

cout <<"The size of int is " <<sizeof(Integer) << " bytes" << endl;

This line outputs the size of an int in bytes, helping to understand how much memory each data type consumes.

The program concludes by returning 0, indicating successful execution. This code snippet is a practical demonstration for beginners to understand the sizes of different data types in C++, which is fundamental in choosing the appropriate type for variables based on the range of values they are expected to hold and the memory efficiency.

Output

The size of int is 4 bytes
The size of short int is 2 bytes
The size of long int is 8 bytes
The size of unsigned int is 4 bytes
The size of unsigned short int is 2 bytes
The size of unsigned long int is 8 bytes
The size of char is 1 bytes
The size of unsigned char is 1 bytes
The size of signed char is 1 bytes
The size of float is 4 bytes
The size of double is 8 bytes
The size of long double is 16 bytes

Process finished with exit code 0