Max Length Concat Unique Chars

Given an array of strings, find the maximum possible length of a concatenated string where no character repeats. You can choose to include or skip each string, but strings containing duplicate characters internally cannot be used.

Examples
Input: ["un","iq","ue"]
Output: 4
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Max Length Concat Unique Chars

Given an array of strings, find the maximum possible length of a concatenated string where no character repeats. You can choose to include or skip each string, but strings containing duplicate characters internally cannot be used.