#include <stdio.h>

main()

{

  int n, count = 1;

  float x, sum = 0,average;

  do {

    printf("how many numbers? ");

    scanf("%d", &n);

    sum = 0;

    count = 1;

    while (count <= n)   {

      printf("x = ");

      printf("\n(to end program, enter 0 for x): ");

      scanf("%f", &x);

      if (x == 0) 

        break;

      sum += x;

      ++count;

    }

    average = sum/n;

    printf("\nthe average is %f\n", average);

  } while (x != 0); 

}