Tower.java

package Question3_4;

import java.util.Stack;

public class Tower {
	private Stack<Integer> disks;
	private int index;
	public Tower(int i) {
		disks = new Stack<Integer>();
		index = i;
	}
	
	public int index() {
		return index;
	}
	
	public void add(int d) {
		if (!disks.isEmpty() && disks.peek() <= d) {
			System.out.println("Error placing disk " + d);
		} else {
			disks.push(d);
		}
	}
	
	public void moveTopTo(Tower t) {
		int top = disks.pop();
		t.add(top);
		System.out.println("Move disk " + top + " from " + index() + " to " + t.index());
	}
	
	public void print() {
		System.out.println("Contents of Tower " + index());
		for (int i = disks.size() - 1; i >= 0; i--) {
			System.out.println("   " + disks.get(i));
		}
	}
	
    public void moveDisks(int n, Tower destination, Tower buffer){
		if (n > 0) {
			moveDisks(n - 1, buffer, destination);
			moveTopTo(destination);
			buffer.moveDisks(n - 1, destination, this);
		}
	}
}