Program to convert binary number to decimal number

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

void main()
{
clrscr();
unsigned long i,n,num=0,d;
cout<<"\n Enter a Binary number(01101) : ";
cin>>n;
cout<<"\n\t Equivalent Decimal Number is : ";

for(i=0;n!=0;++i)
{
d=n%10;
num=(d)*(pow(2,i))+num;
n=n/10;
}
cout<<num;
getch();
}

                                                             Output