#include <iostream.h>

int average(int x, int y)
{ return((x+y)/2);}

int average(int x, int y, int z)
{ return((x+y+z)/3);}

int mystery( int a, int b,  int (* fn)(int, int, int))
{    return( fn(a,b,3*b) );  }

int main()
{ int i;
        i= mystery( 8, 9, average);
        cout << "i = " << i << endl;
        return(0);
}