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$ curl repovive.com/roadmaps/data-structures/arrays-prefix-sums/longest-substring-implementation

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$ curl repovive.com/roadmaps/data-structures/arrays-prefix-sums/longest-substring-implementation

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Longest Substring - Implementation - Arrays & Prefix Sums | Data Structures | Repovive

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Data Structures19 sections · 729 units49h total

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Longest Substring - Implementation

Complete solution

Here's the solution:

function lengthOfLongestSubstring(s)
    charSet := empty set
    left := 0
    maxLength := 0

    for right from 0 to length of s - 1
        // Shrink window until no repeat
        while s[right] is in charSet
            remove s[left] from charSet
            left := left + 1

        // Expand window
        add s[right] to charSet
        maxLength := max(maxLength, right - left + 1)

    return maxLength

Time: $O(n)$ . Space: $O(min(n, m))$ where $m$ is the character set size.