C Program for Base Conversion from Binary to Decimal

#include<stdio.h>
#include<conio.h>
int power (int);
void main()
{
long int n;
int x,s=0,i=0,flag=1;
clrscr();
printf("Input a Binary Number\n\n");
scanf("%ld",&n);
while(flag==1)
{
x=n%10;
s=s+x*power(i);
i=i+1;
n=n/10;
if(n==0)
flag=0;
}
printf("\nDecimal Equivalent = %d",s);
getch();
}
power(int i)
{
int j,p=1;
for(j=1;j<=i;j++)
p = p*2;
return(p);
}