What is the optimal time complexity of solving Longest Palindromic Substring?

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 Palindromic Substring?

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 Palindromic Substring?

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 Palindromic Substring?

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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Competitive ProgrammingEasy

Longest Palindromic Substring

Learn how to solve the 'Longest Palindromic Substring' problem. This detailed resource details brute force and optimized approaches.

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Problem Statement

Easy

Given a string s, return the longest palindromic substring in s.

Write a function longestPalindrome(s: str) -> str.

Constraints

•1 <= len(s) <= 1000
•s consists of only digits and English letters

Examples

Example 1

Input

s = "babad"

Output

"bab"

Explanation

"aba" is also a valid answer.

Example 2

Input

s = "cbbd"

Output

"bb"

Explanation

The longest palindromic substring is "bb".

Need a Hint?

Define subproblem states, establish the recurrence relation, and use memoization (top-down) or tabulation (bottom-up).

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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