#include<iostream>

using namespace std;
#define MAX 1000

int main()
{
    char binaryNumber[MAX],hexaDecimal[MAX];
    long int i=0;

    cout<<"Enter any hexadecimal number: ";
    cin>>hexaDecimal;

    cout<<"\nEquivalent binary value: ";
    while(hexaDecimal[i])
    {
         switch(hexaDecimal[i])
         {
             case '0': cout<<"0000"; break;
             case '1': cout<<"0001"; break;
             case '2': cout<<"0010"; break;
             case '3': cout<<"0011"; break;
             case '4': cout<<"0100"; break;
             case '5': cout<<"0101"; break;
             case '6': cout<<"0110"; break;
             case '7': cout<<"0111"; break;
             case '8': cout<<"1000"; break;
             case '9': cout<<"1001"; break;
             case 'A': cout<<"1010"; break;
             case 'B': cout<<"1011"; break;
             case 'C': cout<<"1100"; break;
             case 'D': cout<<"1101"; break;
             case 'E': cout<<"1110"; break;
             case 'F': cout<<"1111"; break;
             case 'a': cout<<"1010"; break;
             case 'b': cout<<"1011"; break;
             case 'c': cout<<"1100"; break;
             case 'd': cout<<"1101"; break;
             case 'e': cout<<"1110"; break;
             case 'f': cout<<"1111"; break;
             default:  cout<<"\nInvalid hexadecimal digit "<<hexaDecimal[i];
         }
         i++;
    }

    return 0;
}