Convert Octal to Hexadecimal Program in C++

C++ program to Convert Octal to Hexadecimal

To convert Octal number to Hexadecimal number in C++ programming, We have to ask to the user to enter the Octal number to convert it into Hexadecimal number to display the equivalent value in Hexadecimal format on screen.
When converting from octal to hexadecimal, it is often easier to first convert the octal number into binary and then from binary into hexadecimal.

Hex / decimal / octal / binary conversion table

Input Octal Number : 10
Euivalent Hexadecimal Number : 8

Input Octal Number : 6
Euivalent Hexadecimal Number : 6

Input Octal Number : 11
Euivalent Hexadecimal Number : 9

#include<iostream.h>
#include<conio.h>
#include<math.h>

int main()
{
    int OCTALVALUES[] = {0, 1, 10, 11, 100, 101, 110, 111};

    long long octal, temp_Octal, binary, place;
    char hex[65] = "";
    int rem;

    place = 1;
    binary = 0;
    clrscr();    

    cout<<"Please Enter any Octal Number: ";
    cin>>octal;
    temp_Octal = octal;

    // First Convert Octal to Binary
     
    while(temp_Octal > 0)
    {
        rem = temp_Octal % 10;
        binary = (OCTALVALUES[rem] * place) + binary;
        temp_Octal /= 10;

        place *= 1000;
    }
    
    // Convert Binary to Hexadecimal
    
    while(binary > 0)
    {
        rem = binary % 10000;
        switch(rem)
        {
            case 0:
                strcat(hex, "0");
                break;
            case 1:
                strcat(hex, "1");
                break;
            case 10:
                strcat(hex, "2");
                break;
            case 11:
                strcat(hex, "3");
                break;
            case 100:
                strcat(hex, "4");
                break;
            case 101:
                strcat(hex, "5");
                break;
            case 110:
                strcat(hex, "6");
                break;
            case 111:
                strcat(hex, "7");
                break;
            case 1000:
                strcat(hex, "8");
                break;
            case 1001:
                strcat(hex, "9");
                break;
            case 1010:
                strcat(hex, "A");
                break;
            case 1011:
                strcat(hex, "B");
                break;
            case 1100:
                strcat(hex, "C");
                break;
            case 1101:
                strcat(hex, "D");
                break;
            case 1110:
                strcat(hex, "E");
                break;
            case 1111:
                strcat(hex, "F");
            break;
        }

        binary /= 10000;
    }

    strrev(hex);

    cout<<" Equivalent Hexadecimal number: "<< hex;

  getch();
}

Enter any Octal Number: 15
Equivalent Hexadecimal Value is: D