{"blocks": [{"key": "6e0d88e4", "text": "Question", "type": "header-two", "depth": 0, "inlineStyleRanges": [], "entityRanges": [], "data": {}}, {"key": "d1bb93bd", "text": "Given an organizational hierarchy tree, return the lowest common organization (parent node) for two or more employees (≥2). Provide unit tests, detail your tree representation, and discuss how to support dynamic additions and deletions of users/groups with thread-safety considerations.", "type": "unstyled", "depth": 0, "inlineStyleRanges": [], "entityRanges": [], "data": {}}], "entityMap": {}}