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longestUniqueString

Language/Type: Java algorithms interview strings
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Write a method named longestUniqueString that accepts a string as a parameter and returns an integer representing the longest substring that can be formed from it without any repeated characters. For example, the call of longestUniqueString("abcabcab") should return 3 because its longest such substring is "abc". The call of longestUniqueString("aaaa") should return 1 because its longest such substring is "a". The call of longestUniqueString("abbbcbbbacddb") should return 4 because its longest such substring is "bacd". ("abcd" or "abcde" are not valid because they are subsequences, not substrings.)

If the string is empty, return 0. You may assume that the string contains only standard ASCII characters (no extended Unicode character values).

Method: Write a Java method as described, not a complete program or class.

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