public class Tree1 {
    
    public static void main(String[] args) {
	int height = 3;
	int nodes = (int) (Math.pow(2,height)-1);
	Person[] ps = new Person[nodes];
	
	// Array of people:
	for (int i = 0; i < nodes-1; i++)
	    ps[i]=new Person("p"+i);
	
	// Build tree of people:
    
	/*          0              p
		  /   \           / \
	         1     2         m   f
		/ \   / \
               3   4 5   6 
	*/
	
	ps[0].mother = ps[1];
	ps[0].mother = ps[2];

	ps[1].mother = ps[3];
	ps[1].mother = ps[4];

	ps[2].mother = ps[5];
	ps[2].mother = ps[6];

	// count people....?
	
    }
}

class Person {
    public String name;
    public Person father;
    public Person mother;
    public Person(String name) {this.name=name;}
    public String toString() {return name;}
}