#include <stdio.h>
#define NUM_SCORE 5
#define MAX_SCORE 102
#define MIN_SCORE 0

void getScores (int a[]);
double average (int a[]);
void bubbleSort (int a[]);
void swap (int *p, int*q);

main()
{
      int firstRun = 1, i;
      char repeat = 's';
      int a[NUM_SCORE];


      do
      {
                   if (!firstRun)
                   {
                                 getScores(a);
                   }
                   if (firstRun)
                   {
                                a[0] = 72;
                                a[1] = 78;
                                a[2] = 82;
                                a[3] = 88;
                                a[4] = 99;
                                firstRun--;
                   }
                   printf("     Array:     ");
                   for ( i=0 ; i<NUM_SCORE ; i++)
                       printf("%d ", a[i]);
                   printf("\n     Average:   %.2lf\n", average(a));
                   bubbleSort (a);
                   printf("     Sorted:    ");
                   for ( i=0 ; i<NUM_SCORE ; i++)
                       printf("%d ", a[i]);
                   printf("\n     Highest:   %d", a[NUM_SCORE-1]);

                   printf("\nWant to calculate midterm scores?");
                   repeat = getchar();
                   getchar();
       }while(repeat != 'n' && repeat != 'N');
}
double average (int a[])
{
       double average, sum = 0;
       int i;
       for ( i=0 ; i<NUM_SCORE ; ++i)
           sum = sum + a[i];
       average = (sum/NUM_SCORE);

       return average;
}

void bubbleSort (int a[])
{
     int i, j;
     for(i = 0 ; i < NUM_SCORE-1 ; ++i)
           for(j = NUM_SCORE-1 ; i<j ; --j)
                 if( a[j-1] > a[j])
                     swap(&a[j-1], &a[j]);
}

void swap (int *p, int*q)
     /* swap stores the addresses of two numbers passed as paramters to p and q
        then swaps the two values stored by the two addresses by storing the
        dereferenced value in a placer then assigning the value at p to the
        value at q. Then the value at q is changed to the value at p by assigning
        it to placer which was previously stored as the value at p. This effectively
        switches the values stored at the addresses.*/
{
     double placer;
     placer = *p;
     *p = *q;
     *q = placer;
     return;
}

void getScores (int a[])
{
     int tmp, yes, i;
     do
     {
          yes = 1;
          printf("\nEnter 5 midterm scores (0-102):");
          for ( i=0 ; i<NUM_SCORE ; i++)
          {
                scanf("%d", tmp);
                if (tmp <= MIN_SCORE || tmp >= MAX_SCORE)
                {
                        printf("\nERROR! Enter legal scores in the range (0-102)");
                        yes--;
                }
                if (yes)
                {
                        &a[i] = tmp;
                }
          }
     }while(!yes);

}