123. Encode and Decode Strings

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Example 1:

Input: strs = ["lint", "code", "love", "you"]

Output: ["lint", "code", "love", "you"]

Explanation: The `encode` function converts the input array into '4#lint4#code4#love3#you'. The `decode` function then reconstructs the original array from this encoded string.

Example 2:

Input: strs = ["we", "say", ":", "yes"]

Output: ["we", "say", ":", "yes"]

Explanation: The encoded string is '2#we3#say1#:3#yes', which is correctly decoded back to the original list.

Example 3:

Input: strs = ["", ""]

Output: ["", ""]

Explanation: Empty strings are handled correctly; the encoded string becomes '0##0##', which decodes back into an array of two empty strings.

Example 4:

Input: strs = []

Output: []

Explanation: If the input array is empty, the encoded string is an empty string, which decodes back into an empty array.

Example 5:

Input: strs = ["hello world", "!"]

Output: ["hello world", "!"]

Explanation: The encoded string is '11#hello world1#!', and decoding it returns the initial list.

Constraints:

Time Complexity

O(n)

Space Complexity

O(1)