Q. Octal to Decimal conversions ?

THE OUTPUT WOULD BE

#include<stdio.h>
#include<conio.h>
#include<math.h>
  void main( )
  { clrscr( );
long int a[10],i=0,j,c=0,n,s=0;
printf("Enter the Octal number : ");
scanf("%ld",&n);
while(n!=0)
{ a[i]=n%10;
               n=n/10;
               c++;
               i++;
}
for(i=0;i<c;i++)
{ n=a[i]*pow(8,i);
               s=s+n;
}
printf("Octal to Decimal conversion is %ld",s);
getch( );
  }