/*
 * Store student grades in an array.
 * Compute the average of the grades.
 * Read in the grades from the file.
 * CISC105 07.11.05
 * average.4.c
 */

#include<stdio.h>
#define SENTINEL -1
#define MAXGRADES 200

int main() {
  int x = 200;
  float runningSum = 0;
  int grade = 0;
  int numGrades = 0;
  float average;
  int grades[MAXGRADES];
  int i;
  int aboveAvg = 0;
  FILE *file_ptr;

  file_ptr = fopen( "grades.txt", "r");

  if( file_ptr == NULL ) {
    printf("Error opening 'grades.txt'\n");
    exit(1);
  }

  fscanf( file_ptr, "%d", &grade );

  while( grade != SENTINEL ) {
    grades[numGrades] = grade;
    runningSum += grade;
    numGrades++;
    //    printf("Enter a grade or %d to compute the average: ", SENTINEL);
    fscanf(file_ptr, "%d", &grade);
  }

  /* print the saved grades */
  for( i=0; i < numGrades; i++ ) {
    printf("%d\n", grades[i]);
  }

  if( numGrades > 0 ) {
    average = runningSum/numGrades;
    printf("The average of %d grades is %.2f\n", numGrades, average);
  }
  else {
    printf("No grades entered.");
    exit( 1 );
  }

  /*
   * Compute the number of grades that are above average.
   */

  for ( i=0; i < numGrades; i++ ) {
    if( grades[i] > average ) {
      aboveAvg++;
    }
  }
  
  printf("%d grades are above average.\n", aboveAvg );

  return 0;
}