24+ CPP Decimal to Hexadecimal Converters

This post contains a total of 24+ Hand-Picked C++ Decimal to Hexadecimal Converter Examples. All the Decimal to Hexadecimal programs given below are made using C++ Programming language.

You can use the source codes of these programs for your own personal or educational use with credits to the original owner.

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1. By Benjamin Ramirez

Made by Benjamin Ramirez. A simple C++ Program to convert decimal number to hexadecimal number. ( Source )

#include <iostream>
using namespace std;
int dec_to_hex(int num){
    int select = 0,buffer[255];
    if(num == 0){
      cout << "Decimal number " << num << " in hexadecimal is " << num << endl;return 0;
    }
    cout << "Decimal number " << num << " in hexadecimal is ";
    while(num > 15){
        buffer[select] = num % 16;
        num = num / 16;
        select ++;
    }
    if(num < 10){
        cout << num;
        }
        else
        {
            switch(num){
            case 10 : cout << "A" ;break;
            case 11 : cout << "B" ;break; 
            case 12 : cout << "C" ;break;
            case 13 : cout << "D" ;break; 
            case 14 : cout << "E" ;break; 
            case 15 : cout << "F" ;break;
            default : cout << "Switch failed"; return 1; break;
            }
            }
            select --;
    while(select >= 0){
        if(buffer[select] < 10){
            cout << buffer[select];
        }
        else
        {
        switch(buffer[select]){
            case 10 : cout << "A" ;break;
            case 11 : cout << "B" ;break; 
            case 12 : cout << "C" ;break;
            case 13 : cout << "D" ;break; 
            case 14 : cout << "E" ;break; 
            case 15 : cout << "F" ;break;
            default : cout << "Switch failed"; return 1; break;
            }
        }
    select --;
    }
  return 0;    
}
int main() {
int a;
cin >> a;
dec_to_hex(a);
    return 0;
}

2. By nouha coding girl

Made by nouha coding girl. ( Source )

#include <iostream>
using namespace std;
int main()
{
    long int decimalNumber,remainder,quotient;
    int i=1,j,temp;
    char hexadecimalNumber[100];
 
    cout<<"Enter any decimal number: "<<endl;
    cin>>decimalNumber;
 
    quotient = decimalNumber;
 
    while(quotient!=0)
    {
         temp = quotient % 16;
 
      //To convert integer into character
      if( temp < 10)
           temp =temp + 48;
      else
         temp = temp + 55;
 
      hexadecimalNumber[i++]= temp;
      quotient = quotient / 16;
    }
    cout<<"nEquivalent hexadecimal number of "<<decimalNumber<<" is : ";
    for(j = i -1 ;j> 0;j--)
      cout<<hexadecimalNumber[j];
    cout<<endl;
    return 0;
}
 
 

3. By Malek Alsset

Made by Malek Alsset. Change “int n = 282;” to the decimal number you want to use. ( Source )

#include<iostream> 
using namespace std; 
// function to convert decimal to hexadecimal 
void decToHexa(int n) 
{    
    // char array to store hexadecimal number 
    char hexaDeciNum[100]; 
    // counter for hexadecimal number array 
    int i = 0; 
    while(n!=0) 
    {    
        // temporary variable to store remainder 
        int temp  = 0; 
        // storing remainder in temp variable. 
        temp = n % 16; 
        // check if temp < 10 
        if(temp < 10) 
        { 
            hexaDeciNum[i] = temp + 48; 
            i++; 
        } 
        else
        { 
            hexaDeciNum[i] = temp + 55; 
            i++; 
        } 
        n = n/16; 
    } 
    // printing hexadecimal number array in reverse order 

    for(int j=i-1; j>=0; j--) 

        cout << hexaDeciNum[j]; 
} 
int main() 
{ 
    int n = 282; 
    decToHexa(n); 
    return 0; 
} 

4. By Jitendra Pal

Made by Jitendra Pal. ( Source )

#include <iostream>
using namespace std;

int main()
 {
 int a[50],i=1,j,n,t,k;
 cout<<"Enter decimal number:"<<endl;
 cin>>n;
 t=n;
 while(n>0)
 {
     j=n%16;
     a[i]=j;
     i++;
     n=n/16;
 }
 cout<<"Hexadecimal of "<<t<<" is:";
 for(k=i-1;k>=1;k--)
 {
     cout<<a[k];
 }
    return 0;
}

5. By Loved by Everyone

Made by Loved by Everyone. ( Source )

#include <iostream>
#include <string>
using namespace std;

    string decimaltohexadecimal(int n){
        int x=1;
        string ans="";
        
        while(x<=n)
            x*=16;
           x/=16;
        
        while(x>0){
          int lastdigit = n/x;
            n-=lastdigit*x;
            x/=16;
            
            if(lastdigit<=9){
                ans= ans + to_string(lastdigit);
            } else{
                char c= 'A' +lastdigit - 10;
                ans.push_back(c);   
            }
       }
       return ans;
       
    
    } 

int main() {
    
    int n;
    cin>>n;
    
    cout<<decimaltohexadecimal(n)<<endl;
    


    return 0;
}

6. By Kishan Lakhani

Made by Kishan Lakhani. ( Source )

#include<iostream> 
#include<iomanip> 
using namespace std;
int main () 
{ 
cout << hex;
cout<<setiosflags(ios::showbase|ios::uppercase); 
int n;
cin>>n;
cout<<n;
return 0; 

}

7. By Rishu Kumar

Made by Rishu Kumar. Enter the number to be converted in hexadecimal form as input. ( Source )

#include <iostream>
using namespace std;

int main() 
{
   int x;
   cin>>x;
   int a[100];
   int r; int n=x;
   int i=0; int d=0;
  
   while(n!=0)
   {
       r=n%16;
       a[i]=r;
       n=n/16;
       i++; d++;
   }
   i--;
   int b[100];
   int j=0; 
   while(j<d)
   {
       b[j]=a[i];
       j++;
       i--;
   }
   
   cout<<"Number entered: "<<x<<endl;
   cout<<"Hexadecimal form : ";
   i=0;
   while(i<d)
   {
       if(b[i]<10)
        cout<<b[i];
       else
        { char h[]={"ABCDEF"};
          int k=b[i]-10;
           cout<<h[k];
         }
       
       i++;
   }
   
   
    return 0;
}

8. By ๏ผก๏ผฃ๏ผฅ

Made by ๏ผก๏ผฃ๏ผฅ. ( Source )

#include <iostream>
using namespace std;
//convert number to hexadecimal
void HexaDecimal(long long number){
  int remainder;
  int i=0;
  char HexaDecimals[16] = {'0','1','2','3','4',
                           '5','6','7','8',
                           '9','A','B','C',
                           'D','E','F'};
  char result[20];
  while(number!=0){
      remainder = number%16;
      result[i] = HexaDecimals[remainder];
      
      number = number/16;
      i++;
      if(number==0){result[i]='0';}} 
                                     
      bool start = false;            
    for(int k = 9;k>=0;k--){         
        if(result[k]=='0')          
        {start =true;               
        k=k-1;                      
        }                            
        if(start){                   
            cout<<result[k];}}       
        
                                 }
int main() {
  int number;
  cin>>number;
  HexaDecimal(number);
  return 0;
  }

9. By Ashwin

Made by Ashwin. ( Source )

#include <iostream>
using namespace std;
void decToHexa(int n)
{
    char deciToHexa[100];
    int i=0;
    int b;
    b=n;
    while(n!=0)
    {
        int temp=0;
        temp=n%16;
        if(temp<10)
        {
            deciToHexa[i]=temp+48;
            i++;
        }
        else
        {
            deciToHexa[i]=temp+55;
            i++;
        }
        n=n/16;
    }
    
    for(int j=i-1;j>=0;j--)
    {
        
        cout<<deciToHexa[j];
    }
    }

int main() {
int n=2545;
decToHexa(n);

    return 0;
}

10. By Kaushal Ranjan

Made by Kaushal Ranjan. ( Source )

#include<iostream>
using namespace std;
int main ()
{
    int num, temp, i = 1, j, r;
    char hex[50];
    cout << " Enter a decimal number : ";
    cin >> num;
    temp = num;
    while (temp != 0)
    {
        r = temp % 16;
        if (r < 10)
            hex[i++] = r + 48;
        else
            hex[i++] = r + 55;
        temp = temp / 16;
    }
    cout << "\nHexadecimal equivalent of " << num << " is : ";
    for (j = i; j > 0; j--)
        cout << hex[j];
    return 0;
}

11. By Mr AJX

Made by Mr AJX . ( Source )

#include <iostream>

using namespace std;

int main()
{
    int num;

    cout<<"Enter Hexadecimal Number : ";
    cin >> hex >> num;

    cout<<"Decimal number for given hexadecimal number is : ";
    cout << num << endl;

    return 0;
}

12. By Mohammad Kaif

Made by Mohammad Kaif. ( Source )

#include <iostream>
#include <string>
using namespace std;

string reverse(string);
string hex(int);

int main()
{
	int num = 0;
	cout << "Enter a decimal number ";
	cin >> num;
	
	cout << endl << "Decimal " << num << " = Hexadecimal " << hex(num); 
	return 0;
}

string hex(int n)
{
	string ans = "";
	int rem = 0;
	
	if( n == 0)
	{
		ans += n + 48;
	}
	
	while ( n > 0)
	{
		rem = n%16;
		
		if(rem >= 0 && rem <= 9)
		{
			ans += rem + 48;

		}
		else
		{
			ans += rem + 55;
		}
		
		n /= 16;
	}
	
	ans = reverse(ans);
	
	
	
	return ans;
}


string reverse(string ans)
{
	int len = ans.size();
    string mk = ans;
		
	int j = 0; 
	
	for(int i = len-1; i >= 0; i--)
	{
		ans[j] = mk[i];
		j++;
	}
	
	return  ans;
}

13. By Ankit Sharma

Made by Ankit Sharma. A basic C++ program to convert decimal to hexadecimal. ( Source )

#include <bits/stdc++.h>
using namespace std;

//DECIMAL TO HEXADECIMAL

string decimalToHexadecimal (int n){
    int x = 1;
    string ans ="";
    while(x <= n)
    x *= 16;
    x /= 16;
    while(x>0){
        int lastdigit = n/x;
        n -= lastdigit*x;
        x/=16;
        if(lastdigit <= 9){
            ans = ans+ to_string(lastdigit);}
            else {
               char c = 'A' + lastdigit - 10;
               ans.push_back(c);
               }
          }return ans;
}
int main() {int n;
cin >> n;

cout<<decimalToHexadecimal(n)<<endl;

    return 0;
}

14. By Ankit Kumar

Made by Ankit Kumar. ( Source )

#include <iostream>
using namespace std;


void dec2hex(int n);
int main(){
int n;
cin>>n;
dec2hex(n);
    return 0;
}
void dec2hex(int n){
    char arr[100];
    int i=0;
    while(n!=0){
        int temp=0;
        temp = n%16;
        if(temp<10){
            arr[i]=temp+48;
            i++;
        }
        else
        {
            arr[i]=temp+55;
            i++;
        }
        n=n/16;
    }
    
    for(int j=i-1;j>=0;j--)
        cout<<arr[j];
    
}

15. By Jake Nelson

Made by Jake Nelson. Enter an integer and it will be converted into a hexadecimal number as a string. ( Source )

#include <iostream>
#include <string>

using namespace std;

//string in dectohex function is assembled in reverse, so it must be reversed to be used
string reverse(string s)
{
    string rev = "";
    for(int i = s.length(); i >= 0; i--)
    {
        rev += s[i];
    }
    return rev;
}

string decToHex(int d)
{
    char hex[] = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};
    string hexValue = "";
    while (d != 0)
    {
        hexValue += hex[d%16];
        d = d / 16;
    }
    return reverse(hexValue);
}

int main()
{
    int input;
    cout << "please enter a number" << endl;
    cin >> input;
    cout << "the number in decimal: " << input << endl;
    cout << "the number in hex: " << decToHex(input) << endl;
    return 0;
}

16. By ausama.ly

Made by ausama.ly. ( Source )

// Convert Decimal To Hexdecimal.
//---------------------------------
#include <iostream>
using namespace std;

int main()
 {
    int dec , hex ;
    cout << "Enter Number :- ";
    cin >> dec ;
    while(dec>0)
    {
        hex = dec % 16;
        if (hex==10) 
       
        cout << "A" << endl ;
        else if (hex==11)
        cout << "B" << endl ;
        else if (hex==12)
        cout << "C" << endl ;
        else if (hex==13)
        cout << "D" << endl ;
        else if (hex==14)
        cout << "E" << endl ;
        else if (hex==15)
        cout << "F" << endl ;
        else
        cout << hex<< endl ;
        dec = dec / 16 ;
    
    }
    return 0;
}

17. By Pewien Internauta

Made by Pewien Internauta. ( Source )

#include <iostream>
using namespace std;

int main() {
int n;
cin>>n;
if(n<16777216){
    int arr [24];
    int a,x=0;
    int b=8388608;
    cout<<n<<" => ";
    while(x<24){
        arr [x]=(n-a)/b;
        a+=arr[x]*b;
        b/=2;
        cout<<arr[x];
        x++;
    }
    cout<<" => ";
    a=0;
    x=0;
    int ar[6]{0,0,0,0,0,0};
    char ara[6]{'A','B','C','D','E','F'};
    b=16;
    while (a<6){
        b/=2;
        ar[a]+=arr[x]*b;
        x++;
        if(b==1){
            b=16;
            if(ar[a]>9){
                cout<<ara[ar[a]-10];
            }
            else{
                cout<<ar[a];
            }
            a++;
        }
    }
}
else{
    cout <<"Your number is too big";
}
    return 0;
}

18. By Prajwal Yeotkar

Made by Prajwal Yeotkar. ( Source )

#include <iostream>
using namespace std;
int main() 
{
int a,n,rem;
cout<<"Enter the decimal number:";
cin>>a;
for(int i=16;a>=i;a/i)
{
rem = a%16;
a = a/16;
cout<<rem;
}
switch(rem)
{
case 1 : cout<<"1";
break;
case 2 : cout<<"2";
break;
case 3 : cout<<"3";
break;
case 4 : cout<<"4";
break;
case 5 : cout<<"5";
break;
case 6 : cout<<"6";
break;
case 7 : cout<<"7";
break;
case 8 : cout<<"8";
break;
case 9 : cout<<"9";
break;
case 10 : cout<<"A";
break;
case 11 : cout<<"B";
break;
case 12 : cout<<"C";
break;
case 13 : cout<<"D";
break;
case 14 : cout<<"E";
break;
case 15 : cout<<"F";
break;
}


    return 0;
}

19. By Alex Khorunjiy

Made by Alex Khorunjiy. ( Source )

#include <iostream>
using namespace std;

int main() {
int a,d,aa;
cin >> a;
cout << a << " = ";
if (a > 1048576){
    aa =a%1048576;
    d=(a-aa)/1048576;
    if (d<10)
    cout << d;
    switch (d){
        case 10:
        cout << "A";
        break;
        case 11:
        cout << "B";
        break;
        case 12:
        cout << "C";
        break;
        case 13:
        cout << "D";
        break;
        case 14:
        cout << "E";
        break;
        case 15:
        cout << "F";
        break; 
        case 16:
        cout << "10";
        break;
    };
    a=aa;
};
if (a > 65536){
    aa =a%65536;
    d=(a-aa)/65536;
    if (d<10)
    cout << d;
    switch (d){
        case 10:
        cout << "A";
        break;
        case 11:
        cout << "B";
        break;
        case 12:
        cout << "C";
        break;
        case 13:
        cout << "D";
        break;
        case 14:
        cout << "E";
        break;
        case 15:
        cout << "F";
        break;
        case 16:
        cout << "10";
        break;
    };
    a=aa;
};
if (a > 4096){
    aa =a%4096;
    d=(a-aa)/4096;
    if (d<10)
    cout << d;
    switch (d){
        case 10:
        cout << "A";
        break;
        case 11:
        cout << "B";
        break;
        case 12:
        cout << "C";
        break;
        case 13:
        cout << "D";
        break;
        case 14:
        cout << "E";
        break;
        case 15:
        cout << "F";
        break; 
        case 16:
        cout << "10";
        break;
    };
    a=aa;
};
if (a > 256){
    aa =a%256;
    d=(a-aa)/256;
    if (d<10)
    cout << d;
    switch (d){
        case 10:
        cout << "A";
        break;
        case 11:
        cout << "B";
        break;
        case 12:
        cout << "C";
        break;
        case 13:
        cout << "D";
        break;
        case 14:
        cout << "E";
        break;
        case 15:
        cout << "F";
        break;
        case 16:
        cout << "10";
        break;
    };
    a=aa;
};
if (a > 16){
    aa =a%16;
    d=(a-aa)/16;
    if (d<10)
    cout << d;
    switch (d){
        case 10:
        cout << "A";
        break;
        case 11:
        cout << "B";
        break;
        case 12:
        cout << "C";
        break;
        case 13:
        cout << "D";
        break;
        case 14:
        cout << "E";
        break;
        case 15:
        cout << "F";
        break;
        case 16:
        cout << "10";
        break;
    };
    a=aa;
};
if (a >= 0){
    aa =a%1;
    d=(a-aa)/1;
    if (d<10)
    cout << d;
    switch (d){
        case 10:
        cout << "A";
        break;
        case 11:
        cout << "B";
        break;
        case 12:
        cout << "C";
        break;
        case 13:
        cout << "D";
        break;
        case 14:
        cout << "E";
        break;
        case 15:
        cout << "F";
        break; 
        case 16:
        cout << "10";
        break;
    };
};
    return 0;
}

20. By Damon Teichroeb

Made by Damon Teichroeb. ( Source )

#include <iostream>
using namespace std;

#define ASCII_A    55 // ASCII code for the capital letter A.
#define ASCII_ZERO 48 // ASCII code for the number zero.
#define MAX_HEX    16 // Maximum number of hexadecimal digits.

int main()
{
    unsigned long long decimal[MAX_HEX];
    short index = 0;

    // Gets the user's decimal number.
    cin  >> decimal[index];
    
    // Converts the decimal number into a hexadecimal number.
    while (decimal[index] > 0 && index < MAX_HEX)
    {
        if (index < MAX_HEX - 1) decimal[index+1] = decimal[index] / 16;
        decimal[index] = decimal[index] % 16;
        if (decimal[index] > 9) decimal[index] += ASCII_A;
        else                    decimal[index] += ASCII_ZERO;
        index++;
    }
    
    // Checks to see if the first or last index are reached.
    if      (index == 0)       decimal[index] = ASCII_ZERO;
    else if (index == MAX_HEX) index--;

    // Prints the hexadecimal number.
    cout << "Your hexadecimal number is: ";
    for (; index >= 0; index--) cout << (char)decimal[index];

    // Says good-bye and terminates the program.
    cout << "\n\nThanks for using my program!"
         <<   "\nHave a nice day! ;-)"
         << "\n\n\n";
    return 0;
}

21. By Aman Parmar

Made by Aman Parmar. ( Source )

#include <iostream>
using namespace std;

string decimalToHexadecimal(int n){
    int x=1;
    string ans="";
    while(x<=n){
        x*=16;
    }
    x/=16;
    
    while(x>0){
        int lastDigit=n/x;
        n-=lastDigit*x;
        x/=16;
        
        if(lastDigit<=9){
            ans=ans+to_string(lastDigit);
        }else{
            char c='A'+lastDigit-10;
            ans.push_back(c);
        }
    }
    return ans;
}
int main() {
    int n;
    cin>>n;
    
    cout<<decimalToHexadecimal(n)<<endl;
    
    return 0;
}

22. By mbouchett

Made by mbouchett. Decimal to Hexadecimal using Recursion. ( Source )

/* 
 * File:   main.cpp
 * Author: Mark Bouchett
 *
 * Created on June 30, 2017, 9:26 PM
 * This program uses recursion to convert Decimal to Hexadecimal
 * decToHex() adapted from Ananthan's Blog(gitHub)
 * http://eionix.blogspot.com/2014/12/decimal-to-hex-conversion-using.html
 */

#include <iostream>  //console Input/Output
#include <string>    //string handler
#include "getInt.h"  // fetches an integer
#include <c++/6/iostream>


using namespace std; //declares the name space
// declare function prototypes
void decToHex(int, string &);

int main() {

    getInt x;   // object ensures an integer
    int z = 0;  // container to save returned integer
    string hex; // holds the hex conversion
    
    //intro
    cout << "Decimal to Hexadecimal convertor";
    
    // main program loop
    while(z >= 0){
        cout << "\n\nEnter an integer for conversion or -1 to quit: ";
        hex = "";           //clear the hex container
        x.fetchInt();       //get an integer 
        z = x.returnInt();  //save the integer to z
        decToHex(z, hex);   //invoke the recursive dec to hex function
        
        if(z >=0 ){         //output unless -1 entered
            cout << z << endl;
            cout << hex;
        }else{              //print output message
            cout << "Goodbye!";
        }
    }
    
    return 0;
}

/**
 * converts decimals to hexadecimal using recursion
 * @param n     //decimal to be converted
 * @param hex   //reference to hex string
 */
void decToHex(int n, string& hex){
    
    int dhex = 0;               
    
    if(!n){
        return;                 //Base case
    }else{                      //recursive case
        dhex = n % 16;          //separate the remainder
        decToHex(n/16 , hex);   //recurse minus the remainder
    }
    if(dhex > 9)                //store the over 9 digits A,B,C,D,E & F
        hex += 'A'+(dhex-10);   //Ananthan's clever bit to get the over 9 digits
    else                        //store the under 10 digits
        hex += to_string(dhex);
}

23. By pondps123

Made by pondps123. ( Source )

#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <math.h>
void Hexadecimal(int Num)
{
	int num_hexa, i = 0, j = 0;
	int a[128], * b;
	if (Num > 0)
	{
		while (Num != 0)
		{
			num_hexa = Num % 16;
			a[i] = num_hexa;
			Num /= 16;
			i++;
		}
		b = a;
		i--;
		printf("Hexadecimal Number : ");
		for (i; i >= 0; i--)
		{
			if (*(b + i) < 10) {
				printf("%d", *(b + i));
			}
			else if (*(b + i) == 10) {
				printf("A");
			}
			else if (*(b + i) == 11) {
				printf("B");
			}
			else if (*(b + i) == 12) {
				printf("C");
			}
			else if (*(b + i) == 13) {
				printf("D");
			}
			else if (*(b + i) == 14) {
				printf("E");
			}
			else if (*(b + i) == 15) {
				printf("F");
			}
		}
	}
	else if (Num < 0)
	{
		int NewNum = abs(Num),n = NewNum,j=0;
		while (NewNum != 0)
		{
			num_hexa = NewNum % 16;
			a[i] = num_hexa;
			NewNum /= 16;
			i++;
			j++;
		}
		b = a;
		i--;
		j--;
		printf("Hexadecimal Number (%d) : ", n);
		for (i; i >= 0; i--)
		{
			if (*(b + i) < 10) {
				printf("%d", *(b + i));
				*(b + i) = abs(*(b + i) - 15);
			}
			else if (*(b + i) == 10) {
				printf("A");
				*(b + i) = abs(*(b + i) - 15);
			}
			else if (*(b + i) == 11) {
				printf("B");
				*(b + i) = abs(*(b + i) - 15);
			}
			else if (*(b + i) == 12) {
				printf("C");
				*(b + i) = abs(*(b + i) - 15);
			}
			else if (*(b + i) == 13) {
				printf("D");
				*(b + i) = abs(*(b + i) - 15);
			}
			else if (*(b + i) == 14) {
				printf("E");
				*(b + i) = abs(*(b + i) - 15);
			}
			else if (*(b + i) == 15) {
				printf("F");
				*(b + i) = abs(*(b + i) - 15);
			}
		}
		printf("\n1's complement = ");
		i = j;
		for (i; i >= 0; i--)
		{
			if (*(b + i) < 10) {
				printf("%d", *(b + i));
			}
			else if (*(b + i) == 10) {
				printf("A");
			}
			else if (*(b + i) == 11) {
				printf("B");
			}
			else if (*(b + i) == 12) {
				printf("C");
			}
			else if (*(b + i) == 13) {
				printf("D");
			}
			else if (*(b + i) == 14) {
				printf("E");
			}
			else if (*(b + i) == 15) {
				printf("F");
			}
		}
		*b += 1;
		for (int k = 0; k <= j; k++)
		{
			if (*(b + k) == 16)
			{
				*(b + k) = 0;
				*(b + k + 1) += 1;
			}
		}
		printf("\n2's complement = ");
		for (j; j >= 0; j--)
		{
			if (*(b + j) < 10) {
				printf("%d", *(b + j));
			}
			else if (*(b + j) == 10) {
				printf("A");
			}
			else if (*(b + j) == 11) {
				printf("B");
			}
			else if (*(b + j) == 12) {
				printf("C");
			}
			else if (*(b + j) == 13) {
				printf("D");
			}
			else if (*(b + j) == 14) {
				printf("E");
			}
			else if (*(b + j) == 15) {
				printf("F");
			}
		}
	}
	else if (Num == 0)
	{
		printf("Hexadecimal Number : 0");
	}
}
int main()
{
	int a;
	printf("Enter Decimal Number : ");
	scanf("%d", &a);
	Hexadecimal(a);
	return 0;
}

24. By IdoloD

Made by IdoloD. ( Source )

#include <stdio.h>
#include <stdlib.h>
//IdoloD github
#define DEBUG 1
//IdoloD github
struct hex_struct {
char* nums;
int top;
int size;
};
//https://github.com/IdoloD/convert-decimal-to-hexadecimal
void reverse(char* nums, int top) {
int i;
for(i=0; i < top/2; i++) {
char swap_var = nums[i];
nums[i] = nums[(top-1)-i];
nums[(top-1)-i] = swap_var;
}
//https://github.com/IdoloD/convert-decimal-to-hexadecimal
}
//IdoloD github
int main () {
int dec_num;
struct hex_struct hex_num;
//IdoloD github
hex_num.top = 0;
hex_num.size = 4;
hex_num.nums = (char*)malloc(hex_num.size*sizeof(char));
//IdoloD github
//https://github.com/IdoloD/convert-decimal-to-hexadecimal
//IdoloD github
do {
printf("Enter a decimal positive number: ");//IdoloD github
scanf("%d", &dec_num);
fflush(stdin);
} while (dec_num < 0);
printf("\n\n");
//IdoloD github
while (dec_num > 0) {
//IdoloD github
if(hex_num.top == hex_num.size) {
hex_num.size *= 2;
//IdoloD github
hex_num.nums = (char*)realloc(hex_num.nums, hex_num.size*sizeof(char));
if(DEBUG)
//IdoloD github
printf("[debug] Reallocated memory from %d byte to %d byte\n", hex_num.size/2, hex_num.size);
}
//IdoloD github
int quoz = dec_num % 16;
dec_num /= 16;
//https://github.com/IdoloD/convert-decimal-to-hexadecimal
char char_quoz;
if (quoz < 10)
//IdoloD github
char_quoz = (char)(48+quoz);
else if(quoz >= 10)
char_quoz = (char)(55+quoz);
//https://github.com/IdoloD/convert-decimal-to-hexadecimal
hex_num.nums[hex_num.top] = char_quoz;
hex_num.top++;
//IdoloD github
}
hex_num.nums[hex_num.top] = '\0';
//https://github.com/IdoloD/convert-decimal-to-hexadecimal
reverse(hex_num.nums, hex_num.top);
printf("the number in hexadecimal is: %s\n", hex_num.nums);
//IdoloD github
printf("Press a button to continue...");
getchar();
return 0;
}
//https://github.com/IdoloD/convert-decimal-to-hexadecimal

25. By Charles Wolfe

Made by Charles Wolfe. A program to convert decimal values to hexadecimal. ( Source )

#include "stdafx.h"
#include <iostream>
#include <vector>
#include <map>
#include <string>
#include <regex>

std::string dec_to_hex(int input) {
	std::map<int, std::string> hex;
	hex[10] = "A";
	hex[11] = "B";
	hex[12] = "C";
	hex[13] = "D";
	hex[14] = "E";
	hex[15] = "F";

	std::string output = "";
	std::vector <int> pow_16;
	std::vector <int> place_values;
	int remainder;

	for (int i = 1; i <= input; i *= 16) {
		pow_16.push_back(i);
	}

	for (int i = pow_16.size() - 1; i >= 0; i--) {
		if (input / pow_16[i] == 0) {
			place_values.push_back(input / pow_16[i]);
		}
		else {
			place_values.push_back(input / pow_16[i]);
			input = input % pow_16[i];
		}
	}

	for (int i = 0; i < place_values.size(); i++) {
		if (place_values[i] > 9) {
			output += hex[place_values[i]];
		}
		else {
			output += std::to_string(place_values[i]);
		}
	}
	
	return output;
}

int main()
{
	std::regex non_num("[\\D]{1,}");
	std::string decimal_str;
	int decimal;
	bool again = true;
	
	while (again == true) {
		std::cout << "Enter a decimal number, or press 'q' to quit: ";
		std::cin >> decimal_str;
		if (regex_match(decimal_str, non_num) && decimal_str != "q") {
			std::cout << "\n";
		}
		else if (decimal_str == "q"){
			std::cout << "\n";
			again = false;
		}
		else {
			decimal = std::stoi(decimal_str);
			std::cout << "\nHexadecimal equivalent of " << decimal << ": " << dec_to_hex(decimal) << "\n\n";

			}
		}
		
    return 0;
}