// Source: "Software Design ...", John A Robinson, Newnes, 2004, page 150.
#include <fstream>
#include "loc.h"
#include "mountain.h"

 int main(int argc, char **argv)
    {
    location *ploc;
    if (argc != 2)
       {
       cerr << "Usage: tellzone locationsfile\n";
       return -1;
       }
    ifstream infile(argv[1]);
    if (!infile)
       {
       cerr << "Can't open " << argv[1] << " for reading\n";
       return -1;
       }
    int numrecords;
    infile >> numrecords;
    location current_location;
    ploc = &current_location;	// ploc, a pointer to a location, now points at a location

    int i;
    for (i = 0; i < numrecords; i++)
        {
        ploc->load(infile);
        cout << "Location " << ploc->getname()
             << " is in the " << ploc->zone() << " zone\n";
        }
    infile >> numrecords;
    mountain current_mountain;
    ploc = &current_mountain;  	// A pointer to a base class can point to
                                										// an object of a derived class. So ploc, a
				// pointer to a location now points at a 
				// mountain
    for (i = 0; i < numrecords; i++)
        {
        ploc->load(infile);								// Calling mountain's load method
        cout << "Mountain " << ploc->getname()
             << " is in the " << ploc->zone() << " zone\n";
	// The previous two lines call location's
	// getname and zone methods, which mountain inherits
        }
    infile.close();
    return 1;
    }