Integers in C++ are converted to hexadecimal

Converting integers to hexadecimal strings in C++ can be achieved in multiple ways. One common approach is to use the std::stringstream class from the standard library and the std::setiosflags and std::setfill methods from the <iomanip> header. Here, I'll provide an example demonstrating how to achieve this conversion.

Example Code

cpp
#include <iostream>
#include <sstream>
#include <iomanip>

std::string intToHex(int num) {
    std::stringstream ss;
    // Set the output format to hexadecimal
    ss << std::hex << num;
    return ss.str();
}

int main() {
    int number = 255;
    std::string hexStr = intToHex(number);
    std::cout << "Integer: " << number << " converted to hexadecimal string is: " << hexStr << std::endl;
    return 0;
}

Code Explanation

1. Header Files:

   • <iostream>: Used for input and output operations.
   • <sstream>: Contains the std::stringstream class for string stream operations.
   • <iomanip>: Used for controlling input and output formatting, such as hexadecimal.

2. intToHex Function:

   • Parameter: Accepts an integer num.
   • Process: Creates a std::stringstream object ss.
   • Set output format: By inserting std::hex into ss, the output format is set to hexadecimal.
   • Output the integer num to ss, converting it to a hexadecimal string.
   • Return the converted string.

3. main Function:

   • Declares an integer variable number initialized to 255.
   • Calls the intToHex function to convert the integer to a hexadecimal string.
   • Outputs the conversion result.

Extended Functionality

If you need to generate a hexadecimal string with a fixed length, such as always producing two-character strings (e.g., 0F, FA), you can use std::setfill and std::setw within std::stringstream to set the fill character and width.

For example:

cpp
ss << std::setfill('0') << std::setw(2) << std::hex << num;

This ensures the output is always a two-digit hexadecimal number, with insufficient digits padded with '0'.

This covers the methods and examples for converting integers to hexadecimal strings in C++.