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Home Queues and Priority Queues The Golfer Class
 
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The Golfer Class

As an example of something with an unusual definition of "highest" priority, we'll use golfers:

class Golfer {

  public:

    pstring name;
    int score;

    Golfer (pstring name, int score) {
        this->name = name;
        this->score = score;
    }
}

The class definition and the constructor are pretty much the same as always.

Since priority queues require some comparisons, we'll have to write a function compareTo. So let's write one:

    int compareTo (Golfer g1, Golfer g2) {

        int a = g1.score;
        int b = g2.score;

        // for golfers, low is good!
        if (a<b) return 1;
        if (a>b) return -1;
        return 0;
    }

Finally, we can create some golfers:

        Golfer* tiger = new Golfer ("Tiger Woods", 61);
        Golfer* phil = new Golfer ("Phil Mickelson", 72);
        Golfer* hal = new Golfer ("Hal Sutton", 69);

And put them in the queue:

        pq.insert (tiger);
        pq.insert (phil);
        pq.insert (hal);

When we pull them out:

        while (!pq.empty ()) {
            golfer = pq.remove ();
            cout << golfer->name << ' ' << golfer->score;
        }

They appear in descending order (for golfers):

        Tiger Woods 61
        Hal Sutton 69
        Phil Mickelson 72

Ok, so now that we've got a priority queue done for golfers...FORE!!!
Home Queues and Priority Queues The Golfer Class

Last Update: 2005-12-05