Program to convert Binary into Decimal number

#include<iostream.h>
#include<conio.h>
#include<math.h>
void main()
{
  int a[10],i,n,sum=0,j,k=0;
  clrscr();
  cout<<"Enter binary number : ";
  cin>>n;
  i=0;
  while(n>0)
  {
      a[i]=n%10;
      n=n/10;
      i++;
  }
  for(j=0;j<i;j++)
  {
      sum=sum+a[j]*pow(2,k);
       k++;
  }
  cout<<"Decimal number is : "<<sum;
  getch();
}