{"blocks": [{"key": "87d0cb69", "text": "Question", "type": "header-two", "depth": 0, "inlineStyleRanges": [], "entityRanges": [], "data": {}}, {"key": "543bed60", "text": "Implement an iterator from scratch in a blank coding environment.", "type": "unstyled", "depth": 0, "inlineStyleRanges": [], "entityRanges": [], "data": {}}, {"key": "660bddd5", "text": "Define the iterator interface manually.", "type": "unordered-list-item", "depth": 0, "inlineStyleRanges": [], "entityRanges": [], "data": {}}, {"key": "3af08e92", "text": "Implement two concrete iterator classes that satisfy three follow-up requirements (e.g., additional traversal features or performance guarantees).", "type": "unordered-list-item", "depth": 0, "inlineStyleRanges": [], "entityRanges": [], "data": {}}, {"key": "633443ed", "text": "Provide unit tests to validate the implementation.", "type": "unordered-list-item", "depth": 0, "inlineStyleRanges": [], "entityRanges": [], "data": {}}], "entityMap": {}}