/*
 * Read and evaluate student test scores
 */
#include <stdio.h>

/* Display a notice regarding average test score
   3 test scores are required as parameters */
void GiveNotice (int score1, int score2, int score3)
{
    /* Are the scores all positive? */
    if (score1 >= 0 && score2 >= 0 && score3 >= 0)
    {
       /* Compute average score */
       double Average = (score1 + score2 + score3) / 3.0; 
       printf ("Average score is %.1f -- ", Average );

       /* Display a message depending on range the score falls in */
       if (Average >= 60.0)
       {
          printf ("Passing");
          if (Average < 70.0)
          {
              printf (" but marginal");
          }
          printf (".");
       }
       else
       {
          printf ("Failing.");
      }
    }
    /* Display invalid data message */
    else
    {
       printf ("Invalid data: score less than zero.");
    }

} 

int main (void)
{
    int IDnum;    /* Student ID number */
    int score1;   /* Score on first test */
    int score2;   /* Score on second test */
    int score3;   /* Score on third test */

    /* Obtain input */
    printf("Enter a Student ID number and three test scores: ");
    scanf ("%d%d%d%d",&IDnum,&score1,&score2,&score3);

    /* Echo the input data */
    printf("Student number: %d \n", IDnum);
    printf("Test Scores: %d %d %d \n",score1,score2,score3 );

    /* Go do the calculations */
    GiveNotice (score1, score2, score3);
    return 0;
}