import java.util.ArrayList;
import java.util.List;
import java.util.Stack;

public class Vertex {
	public Stack<Integer> left;
	public Stack<Integer> middle;
	public Stack<Integer> right;
	public Vertex previous;

	public Vertex(Stack<Integer> left, Stack<Integer> middle, Stack<Integer> right) {
		this.left = left;
		this.middle = middle;
		this.right = right;
		previous = null;
	}

	public List<Vertex> getChildren() {
		List<Vertex> children = new ArrayList<>();
		leftToMiddle(children);
		leftToRight(children);
		middleToLeft(children);
		middleToRight(children);
		rightToLeft(children);
		rightToMiddle(children);
		return children;
	}

	public String toString() {
		StringBuilder sb = new StringBuilder("{");
		sb.append(left.toString());
		sb.append(", ");
		sb.append(middle.toString());
		sb.append(", ");
		sb.append(right.toString());
		sb.append("}");
		return sb.toString();
	}

	private void leftToMiddle(List<Vertex> children) {
		if (!left.isEmpty() && (middle.isEmpty() || left.peek() < middle.peek())) {
			@SuppressWarnings("unchecked")
			Vertex child = new Vertex((Stack<Integer>) left.clone(), (Stack<Integer>) middle.clone(),
					(Stack<Integer>) right.clone());
			child.middle.push(child.left.pop());
			child.previous = this;
			children.add(child);
		}
	}

	private void leftToRight(List<Vertex> children) {
		if (!left.isEmpty() && (right.isEmpty() || left.peek() < right.peek())) {
			@SuppressWarnings("unchecked")
			Vertex child = new Vertex((Stack<Integer>) left.clone(), (Stack<Integer>) middle.clone(),
					(Stack<Integer>) right.clone());
			child.right.push(child.left.pop());
			child.previous = this;
			children.add(child);
		}
	}

	private void middleToLeft(List<Vertex> children) {
		if (!middle.isEmpty() && (left.isEmpty() || middle.peek() < left.peek())) {
			@SuppressWarnings("unchecked")
			Vertex child = new Vertex((Stack<Integer>) left.clone(), (Stack<Integer>) middle.clone(),
					(Stack<Integer>) right.clone());
			child.left.push(child.middle.pop());
			child.previous = this;
			children.add(child);
		}
	}

	private void middleToRight(List<Vertex> children) {
		if (!middle.isEmpty() && (right.isEmpty() || middle.peek() < right.peek())) {
			@SuppressWarnings("unchecked")
			Vertex child = new Vertex((Stack<Integer>) left.clone(), (Stack<Integer>) middle.clone(),
					(Stack<Integer>) right.clone());
			child.right.push(child.middle.pop());
			child.previous = this;
			children.add(child);
		}
	}

	private void rightToLeft(List<Vertex> children) {
		if (!right.isEmpty() && (left.isEmpty() || right.peek() < left.peek())) {
			@SuppressWarnings("unchecked")
			Vertex child = new Vertex((Stack<Integer>) left.clone(), (Stack<Integer>) middle.clone(),
					(Stack<Integer>) right.clone());
			child.left.push(child.right.pop());
			child.previous = this;
			children.add(child);
		}
	}

	private void rightToMiddle(List<Vertex> children) {
		if (!right.isEmpty() && (middle.isEmpty() || right.peek() < middle.peek())) {
			@SuppressWarnings("unchecked")
			Vertex child = new Vertex((Stack<Integer>) left.clone(), (Stack<Integer>) middle.clone(),
					(Stack<Integer>) right.clone());
			child.middle.push(child.right.pop());
			child.previous = this;
			children.add(child);
		}
	}

	public int hashCode() {
		return toString().hashCode();
	}

	public boolean equals(Object other) {
		if (other instanceof Vertex) {
			return toString().equals(((Vertex) other).toString());
		}
		return false;
	}
}