HW17    A generic maximum function

Write a function, gmax(), that is a generic function which
finds the maximum of an array of any type.  The function
receives a pointer to an array, a count of the number
of elements in the array, an int which is the size (in bytes)
of the type of the elments in the array and a pointer to
a function, int compar(void *v1,void *v2).  The latter function
compares two values of the appropriate type and returns
a integer greater than 0 if v1 > v2, an integer less than
0 if v1 < v2, and 0 if v1 == v2.  The generic function gmax()
returns a pointer to the element of lowest index that is the
maximum in the array.


Examples of usage:

        int cmp2ints(void *,void *);
        int newa[100];
        int *pmax;

        pmax = (int *)gmax(newa,100,sizeof(int),cmp2ints);
        fprintf(stdout,"Maximum = %d\n",*pmax);


or

        int cmp2dbls(void *,void *);
        double dare[3000];
        double *dmax;

        dmax = (double *)gmax(dare,3000,sizeof(double),cmp2dbls);
        fprintf(sidout,"maximum = %12.6lf\n",*dmax);

To test your generic maximum function you will need to write a
compar() function.  See the examples in our textbook.  However,
you will only be submitting gmax() to toteach.

What to submit to toteach:

        gmax.c and gmax.h