Convert Hexadecimal to Decimal Program in C++

C++ program to Convert Hexadecimal to Decimal

To convert Hexadecimal number to Decimal number in C++ programming, We have to ask to the user to enter the hexadecimal number to convert it into Decimal number to display the equivalent value in binary format on screen.

0=0000
1=0001
2=0010
3=0011
4=0100
5=0101
6=0110
7=0111
8=1000
9=1001
A=10
B=11
C=12
D=13
E=14
F=15

Input Hexadecimal Number : 2E
Euivalent Decimal Number : 46

Input Hexadecimal Number : 1B
Euivalent Decimal Number : 27

Input Hexadecimal Number : CC
Euivalent Decimal Number : 204

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

void main ()
{
    char num[20];
    int i, r, len, hex = 0;
    clrscr();
    cout<<"Enter any Hexadecimal Number : ";
    cin>>num;
    len = strlen(num);
    for (i = 0; num[i] != '\0'; i++)
    {
        len--;
        if(num[i] >= '0' && num[i] <= '9')
            r = num[i] - 48;
        else if(num[i] >= 'a' && num[i] <= 'f')
                r = num[i] - 87;
             else if(num[i] >= 'A' && num[i] <= 'F')
                    r = num[i] - 55;
        hex += r * pow(16,len);
    }
    cout<<"\nEquivalent Decimal Value " << num << " is : " << hex;
    getch();
}

Enter any Hexadecimal Number: 2B
Equivalent Decimal Value is: 43