Hexadecimal to Binary Conversion

/* C++ Program for Hexadecimal to Binary Conversion */  
#include<bits/stdc++.h>  
using namespace std;  
int main()  
{  
    /* Scan the hexadecimal Number */  
    string Hexadecimal;  
    cout<<"Enter the Hexadecimal Number: ";  
    cin>>Hexadecimal;  
      
    /* Converting Hexadecimal to Binary*/  
    string Binary;  
    /* Converting each digit of hexadecimal number 
       to 4-digit binary number and store the  
       combined result into 'Binary'  
    */  
    for(int i = 0; i < Hexadecimal.length(); i++)  
    {  
        string temp;  
        switch(Hexadecimal[i])  
        {  
            case '0': temp = "0000";  
            break;  
            case '1': temp = "0001";  
            break;  
            case '2': temp = "0010";  
            break;  
            case '3': temp = "0011";  
            break;  
            case '4': temp = "0100";  
            break;  
            case '5': temp = "0101";  
            break;  
            case '6': temp = "0110";  
            break;  
            case '7': temp = "0111";  
            break;  
            case '8': temp = "1000";  
            break;  
            case '9': temp = "1001";  
            break;  
            case 'A': temp = "1010";  
            break;  
            case 'B': temp = "1011";  
            break;  
            case 'C': temp = "1100";  
            break;  
            case 'D': temp = "1101";  
            break;  
            case 'E': temp = "1110";  
            break;  
            case 'F': temp = "1111";  
        }  
        /* Combining the 4-digit binary numbers */  
        Binary = Binary + temp;  
    }  
      
    /* Truncating Extra 0s from beginning, if any */  
    while(Binary[0]=='0')  
    {  
        Binary.erase(Binary.begin()+0);  
    }  
      
    /*Printing the result */  
    cout<<"The Binary of "<<Hexadecimal<<" is "<<Binary;  
}