{ "data": { "question": { "questionId": "1360", "questionFrontendId": "1239", "boundTopicId": null, "title": "Maximum Length of a Concatenated String with Unique Characters", "titleSlug": "maximum-length-of-a-concatenated-string-with-unique-characters", "content": "

You are given an array of strings arr. A string s is formed by the concatenation of a subsequence of arr that has unique characters.

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Return the maximum possible length of s.

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A subsequence is an array that can be derived from another array by deleting some or no elements without changing the order of the remaining elements.

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Example 1:

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\nInput: arr = ["un","iq","ue"]\nOutput: 4\nExplanation: All the valid concatenations are:\n- ""\n- "un"\n- "iq"\n- "ue"\n- "uniq" ("un" + "iq")\n- "ique" ("iq" + "ue")\nMaximum length is 4.\n
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Example 2:

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\nInput: arr = ["cha","r","act","ers"]\nOutput: 6\nExplanation: Possible longest valid concatenations are "chaers" ("cha" + "ers") and "acters" ("act" + "ers").\n
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Example 3:

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\nInput: arr = ["abcdefghijklmnopqrstuvwxyz"]\nOutput: 26\nExplanation: The only string in arr has all 26 characters.\n
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Constraints:

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Most standard library headers are already included automatically for your convenience.

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OpenJDK 17 . Java 8 features such as lambda expressions and stream API can be used.

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C# 10 with .NET 6 runtime

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