Longest Unique Subarray

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Problem statement

You are a developer at a text processing company, and you've been tasked with a feature that identifies the longest segment of a document that contains no repeated characters. This is useful for data validation and linguistic analysis.

A "subarray" or "substring" is a contiguous sequence of characters. For example, in the string "abac", "aba" is a substring, but "aac" is not.

Given an input string s, your task is to find the length of the longest substring that contains only distinct (unique) characters.

Detailed explanation ( Input/output format, Notes, Images )

Input Format:

The input consists of a single line containing the string s.

Output Format:

The output should be a single integer representing the length of the longest substring with all distinct characters.

Note:

If the input string is empty, the longest such substring has a length of 0.

If all characters in the string are the same, the longest such substring has a length of 1.

Sample Input 1:

abacdeab

Sample Output 1:

Explanation for Sample 1:

The input string is "abacdeab". We can examine all substrings with unique characters:
 - "ab" (length 2)
 - "bac" (length 3)
 - "acde" (length 4)
 - "bacde" (length 5)
 - "cdeab" (length 5)
 The maximum length among these is 5.

Sample Input 2:

aaaaa

Sample Output 2:

Explanation for Sample 2:

The only substring with distinct characters is any single character "a". The length is 1.

Expected Time Complexity:

The expected time complexity is O(N), where N is the length of the string.

Constraints:

0 <= n <= 10^5, where n is the length of s.
s consists of lowercase English letters.

Time limit: 1 sec

Approaches (1)

Approach 1

Sliding Window with Hash Set

Time Complexity

Space Complexity

(100% EXP penalty)

Longest Unique Subarray

Console