C++ Exercises: Convert a decimal number to hexadecimal number

Last update on April 07 2025 12:59:18 (UTC/GMT +8 hours)

71. Decimal to Hexadecimal Conversion

Write a program in C++ to convert a decimal number to a hexadecimal number.

Visual Presentation:

C++ Exercises: Convert a decimal number to hexadecimal number

Sample Solution:-

C++ Code :

#include <iostream> // Include input/output stream library
#include <math.h> // Include math library for mathematical functions
using namespace std; // Use the standard namespace

int main() // Main function where the execution of the program starts
{
    int dec_num, r; // Declare integer variables 'dec_num' for decimal number and 'r' for remainder
    string hexdec_num=""; // Declare an empty string 'hexdec_num' to store the hexadecimal number
    char hex[] = {'0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F'}; // Array 'hex' containing hexadecimal characters

    cout << "\n\n Convert a decimal number to hexadecimal number:\n"; // Display message prompting for decimal to hexadecimal conversion
    cout << "---------------------------------------------------\n"; // Display separator line
    cout << " Input a decimal number: "; // Prompt user to input a decimal number
    cin >> dec_num; // Read the decimal number input by the user

    while (dec_num > 0) { // Loop to convert decimal number to hexadecimal
        r = dec_num % 16; // Calculate the remainder when divided by 16 (hexadecimal base)
        hexdec_num = hex[r] + hexdec_num; // Store the corresponding hexadecimal character in 'hexdec_num'
        dec_num = dec_num / 16; // Update 'dec_num' by dividing it by 16 (hexadecimal conversion process)
    }

    cout << " The hexadecimal number is : " << hexdec_num << "\n"; // Display the converted hexadecimal number
}

Sample Output:

 Convert a decimal number to hexadecimal number:                       
---------------------------------------------------                    
 Input a decimal number: 43                                            
 The hexadecimal number is : 2B

Flowchart:

For more Practice: Solve these Related Problems:

Write a C++ program to convert a given decimal number into its hexadecimal equivalent using iterative division.
Write a C++ program that reads a decimal integer and prints its hexadecimal representation by mapping remainders to hex digits.
Write a C++ program to compute the hexadecimal form of a decimal number and display it using uppercase letters.
Write a C++ program that converts a decimal number to hexadecimal using recursion and prints the resulting string.

C++ Code Editor:

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