What is the optimal time complexity of solving Longest Substring Without Repeating Characters?

The optimized solution achieves a time complexity of O(n) by using sorting, mathematical shortcuts, or hash table lookups.

What is the auxiliary space complexity for Longest Substring Without Repeating Characters?

The space complexity is O(1) since we only use a minimal/constant amount of extra memory for tracking variables (or auxiliary space if dynamic structures are allocated).

What are the typical edge cases we must handle in Longest Substring Without Repeating Characters?

Key edge cases include empty collections, negative or large bounds causing integer overflow, arrays with only one element, or inputs where target criteria are not met.

How can we optimize the brute force approach for Longest Substring Without Repeating Characters?

Brute force methods often inspect all possible combinations. We optimize this by sorting the input list to enable binary search, or tracking processed items in a set to avoid redundant nested loop lookups.

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Longest Substring Without Repeating Characters

Learn how to solve the 'Longest Substring Without Repeating Characters' problem. This detailed resource details brute force and optimized approaches.

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Problem Statement

Easy

Given a string s, find the length of the longest substring without repeating characters.

Write a function lengthOfLongestSubstring(s: str) -> int.

Constraints

•0 <= len(s) <= 5 * 10^4
•s consists of English letters, digits, symbols, and spaces

Examples

Example 1

Input

s = "abcabcbb"

Output

Explanation

The answer is "abc", with a length of 3.

Example 2

Input

s = "bbbbb"

Output

Explanation

The answer is "b", with a length of 1.

Example 3

Input

s = "pwwkew"

Output

Explanation

The answer is "wke", with a length of 3. Note that "pwke" is a subsequence, not a substring.

Need a Hint?

Maintain a sliding window boundary using two pointers. Expand the right boundary, and contract the left boundary if criteria are violated.

Edge Cases to Watch

Empty list or null input variables
Single item lists/arrays
Extremely large input bounds causing integer or stack overflow

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