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Encode and Decode Strings - Medium DSA Problem | Thita.ai
Encode and Decode Strings
Difficulty: Medium
Category: DSA
Topics: Array, String, Design
Asked at: Microsoft
You are given a list of strings `strs`, where each string may contain any of the 256 valid ASCII characters (including special characters and empty strings). Your task is to implement two methods:
- `encode(strs)`: Encodes the list of strings into a single string.
- `decode(s)`: Decodes the single string back into the original list of strings.
The encoded string produced by `encode` must contain all the information necessary to reconstruct the original list exactly, even if some strings are empty or contain special characters. You are **not allowed** to use any built-in serialization methods (such as `eval`).
**Constraints:**
- `1 <= strs.length <= 200`
- `0 <= strs[i].length <= 200`
- Each `strs[i]` may contain any ASCII character.
Return the encoded string from `encode`, and the decoded list of strings from `decode`.