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public static <T> void preOrderVisitWRec(BinaryTree.TreeNode<T> treeNode, Visitor<T> visitor) {
        if (treeNode == null) {
            return;
        }
        int level = 0;
        Stack<BinaryTree.TreeNode<T>> stack = new Stack<>();
        stack.push(treeNode);
        while (!stack.isEmpty()) {
            BinaryTree.TreeNode<T> rightBro;
            treeNode = stack.pop();
            visitor.visit(treeNode.getValue(), level);

            if (treeNode.getRight() != null) {
                stack.push(treeNode.getRight());
            }
                rightBro = treeNode.getRight();


            if (treeNode.getLeft() != null) {
                stack.push(treeNode.getLeft());
                level++;
            }
            treeNode = treeNode.getLeft();
            if (rightBro == null && treeNode == null) {
                level--;
            }
        }
    }


public static <T> void inOrderVisitWRec(BinaryTree.TreeNode<T> treeNode, Visitor<T> visitor) {
        Stack<BinaryTree.TreeNode<T>> stack = new Stack<>();
        int level = 0;

        if (treeNode != null) {
            stack.push(treeNode);
            treeNode = treeNode.getLeft();
        }

        while (treeNode != null || !stack.isEmpty()) {
            while (treeNode != null) {
                stack.push(treeNode);
                level++;
                treeNode = treeNode.getLeft();
            }

            treeNode = stack.pop();
            visitor.visit(treeNode.getValue(), level);
            level--;
            treeNode = treeNode.getRight();
            if (treeNode != null ) {
                level++;
            }
        }
    }


public static <T> void postOrderVisitWRec(BinaryTree.TreeNode<T> treeNode, Visitor<T> visitor) {
        Stack<BinaryTree.TreeNode<T>> stack = new Stack<>();
        BinaryTree.TreeNode<T> lastVisitedNode = null;

        while (!stack.isEmpty() || treeNode != null) {
            if (treeNode != null) {
                stack.push(treeNode);
                treeNode = treeNode.getLeft();
            } else {
                BinaryTree.TreeNode<T> peekNode = stack.peek();
                if (peekNode.getRight() != null && lastVisitedNode != peekNode.getRight()) {
                    treeNode = peekNode.getRight();
                } else {
                    visitor.visit(peekNode.getValue(), 0);
                    lastVisitedNode = stack.pop();
                }
            }
        }
    }