C Example

#include <stdio.h>

#define NUM_STUDENTS 25
#define NUM_TESTS 10

int get_highest(int a[][NUM_TESTS], int row, int col);
int *p;



 union {
              int u_i;
      }var;

/* Define a type point to be a struct with integer members hi, fa */
typedef struct {
   int    hi;
   int    fa;
} score;


int factorial(int f);


typedef enum
{  Poor,
   Average,
   Good
} myenum;


int main()
{
   char* test[]={"Poor","Average", "Good"};

   int grades[NUM_STUDENTS][NUM_TESTS] = { {5, 6, 4},
                                           {8, 9, 7} };
   int num_students = 2;
   int num_tests = 3;
   int high_test;
   int grade;
   score student; //define a variable student of type score

   p = &var.u_i;         /* initialise pointer */

   high_test = get_highest( grades, num_students, num_tests);

   *p = factorial(high_test); //use the pointer to change the value of highest_test

   //store variables inside the structure
   student.hi=high_test;
   student.fa=var.u_i;

   myenum value=Average;
   char tmp[0]={0x0};

   printf("The highest score is %d.\n", student.hi);
   printf("This has a factorial of %d.\n",student.fa);

   if(student.hi>0 && student.hi<=4) {grade=0;}
   else if(student.hi>4 && student.hi<=6) {grade=1;}
   else {grade=2;}

   strcpy(tmp,test[grade]); //grade score of student here
   printf("Final Grading is %s.\n",tmp);

   return 0;
}

int get_highest(int a[][NUM_TESTS], int row, int col)
/* Assumes that there is at least one element */
{
   int i, j;
   int highest = a[0][0];

   for( i = 0; i < row; i++)
      for( j = 0; j < col; j++)
         if ( a[i][j] > highest)
            highest = a[i][j];
   return highest;
}



int factorial(int number)
    {
        if (number < 0)
        {
            printf("\nError - negative argument to factorial\n");
            exit(1);
        }
        else if (number == 0)
            return 1;
        else
            return (number * factorial(number - 1));
    }