This question evaluates understanding of trie data structures, serialization/deserialization techniques, parsing robustness including escape handling and malformed input detection, and algorithmic time/space complexity.
Design data structures and algorithms to serialize and deserialize a dictionary trie storing lowercase English words. Specify a compact wire format that supports marking end-of-word, shared prefixes, and arbitrary branching. Implement serialize(root) -> bytes/string and deserialize(data) -> root. Compare DFS vs. BFS encodings, delimiter vs. length-prefix schemes, handling of escape characters, and detection/handling of malformed input. Analyze time and space complexity.