private void drawAux(String indent, StringBuilder builder) {
builder.append(value);
for (List<Node<T>> it = children; !it.isEmpty(); it = it.tail()) {
final boolean isLast = it.tail().isEmpty();
builder.append('\n').append(indent).append(isLast ? "└──" : "├──");
it.head().drawAux(indent + (isLast ? " " : "│ "), builder);
}
}
@Override
public String draw() {
StringBuilder builder = new StringBuilder();
drawAux("", builder);
return builder.toString();
}