function removeHelper(node, val, depth) {

  if (depth === 0 && Object.keys(node.children).length === 0) {

    return true;

  }

​

  let currentChar = val.slice(0, 1);

​

  if (removeHelper(node.children[currentChar], val.slice(1), depth - 1)) {

    delete node.children[currentChar];

    if (Object.keys(node.children).length === 0) {

      return true;

    } else {

      return false;

    }

  } else {

    return false;

  }

}