Q498: Polly the Polynomial

// Run time: 0.530
#include <stdio.h>
#define N 1000
int arr[N];
void calculate(int x, int num);

int main()
{
   int i;
   int num;
   int x;
   while (true)
   {
       for ( i = 0; ; i++)
       {
           if (scanf("%d", &arr[i]) != EOF)
           {
               if (getchar() == '\n')
                   break;
           }
           else
               return 0;
       }
       num = i; // <=

       while (true)
       {
           if (scanf("%d", &x) != EOF)
           {
               calculate(x, num);
               if (getchar() == '\n')
               {
                   putchar('\n');
                   break;
               }
               else
                   putchar(' ');
           }
       }

   }

   return 0;
}

void calculate(int x, int num)
{
   int i, j;
   int sum = 0;
   int product;
   int weight = num;
   for ( i = 0; i <= num; i++)
   {
       product = 1;
       for ( j = 0; j < weight; j++)
           product *= x;
       sum += arr[i]*product;
       weight--;
   }
   printf("%d", sum);
}