{"blocks": [{"key": "0611757a", "text": "Scenario", "type": "header-two", "depth": 0, "inlineStyleRanges": [], "entityRanges": [], "data": {}}, {"key": "295671b9", "text": "Real-time text analytics service enforcing uniqueness constraints", "type": "unstyled", "depth": 0, "inlineStyleRanges": [], "entityRanges": [], "data": {}}, {"key": "984a9197", "text": "Question", "type": "header-two", "depth": 0, "inlineStyleRanges": [], "entityRanges": [], "data": {}}, {"key": "94aca11d", "text": "Implement a Python function returning the length of the longest substring without repeating characters. Follow-up: modify it to return all substrings that meet this criterion.", "type": "unstyled", "depth": 0, "inlineStyleRanges": [], "entityRanges": [], "data": {}}, {"key": "bba5fcb5", "text": "Hints", "type": "header-two", "depth": 0, "inlineStyleRanges": [], "entityRanges": [], "data": {}}, {"key": "9fb1a7f6", "text": "Sliding window with hash map for indices; for follow-up, track start positions and collect substrings of max length.", "type": "unstyled", "depth": 0, "inlineStyleRanges": [], "entityRanges": [], "data": {}}], "entityMap": {}}