public class WalkablesTest 
{
    public static void main(String[] args) 
    {
        Person[] pList = new Person[3];
        pList[0] = new Person("Jack");
        pList[1] = new Person("Jeff"); 
        pList[2] = new Person("John");
        
        // Let every Person walk
        Walkables.letPersonsWalk(pList);
        
        Duck[] dList = new Duck[3];
        dList[0] = new Duck("Donald");
        dList[1] = new Duck("Daisy"); 
        dList[2] = new Duck("Dagobert");
        
        // Let every Duck walk
        Walkables.letDucksWalk(dList);        
    }
}