Back

Longest Palindromic Substring

medium

Given a string s, return the longest substring which is a palindrome.

Test Cases

Copy an input into the main harness and Run to verify
Input
s = "babad"
Expected Output
"bab"

Explanation: "aba" is also a valid answer.

Input
s = "cbbd"
Expected Output
"bb"

Constraints

  • 1 <= s.length <= 1000
  • s consists of only digits and English letters.

Hints

Hint 1 — click to reveal

Expand around each possible center.

Hint 2 — click to reveal

A palindrome center can be a single character OR between two characters (even length).

Java Compiler

Powered by OneCompiler. Starter code loads automatically — edit and hit Run.