Encode & Decode Strings 20 XP Medium

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Design an algorithm to encode a list of strings to a single string, and decode that single string back to the original list of strings.

The trick: prefix each string with its length followed by a delimiter. For example:

['hello', 'world'] → '5#hello5#world'
# 5# means next 5 chars are 'hello'
# 5# means next 5 chars are 'world'

This way, even if strings contain our delimiter character, we can still correctly decode by reading the exact number of characters specified by the length.

📋 Instructions

Implement `encode(strs)` and `decode(s)` functions. Encode `['hello', 'world']`, then decode it back and print the result. Expected output: `['hello', 'world']`

Encode: for each string, prepend len(s) + '#' + s. Decode: read digits until '#', get the length n, then read next n characters as the string.

🧪 Test Cases

Input

decode(encoded)

Expected

['hello', 'world']

Test case 1

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main.py

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Output

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