package euler_tour.expressions;

import euler_tour.EulerTour;
import position.Position;
import tree.binarytree.BinaryTree;

/**
 * Created with MONSTER.
 * User: xgiovio
 * Date: 27/04/2014
 * Time: 13:09
 */
public class EvaluateExpressionTour extends EulerTour<ExpressionTerm,Integer> {

    public Integer execute(BinaryTree<ExpressionTerm> T) {
        init(T);
        return eulerTour(tree.root());
    }

    protected void visitRight(Position<ExpressionTerm> v, TourResult<Integer> r) {
        ExpressionTerm term = v.element();
        if (tree.isInternal(v)) {
            ExpressionOperator op = (ExpressionOperator) term;
            op.setOperands(r.left, r.right);
        }
        r.out = term.getValue();
    }
}