void decode(String encoding, Node root) {
    StringBuilder result = new StringBuilder();
    Node curr = root;
    for (char ch: encoding.toCharArray()) {
        curr = ch == '0' ? curr.left : curr.right;
        if (curr.data != '\0') {
            result.append(curr.data);
            curr = root;
        } 
    }
    System.out.println(result);
}